Major League Baseball

Major League Baseball (MLB) is a professional baseball league in North America made up of 30 teams, evenly split between the National League and the American League. It includes 29 teams in the United States and one in Canada. MLB is regarded as the top professional baseball league globally and one of the major sports leagues in the United States and Canada. Each team plays 162 games in a season, starting with Opening Day in late March or early April. The top six teams from each league compete in a postseason tournament in October, ending with the World Series, a best-of-seven championship that first took place in 1903.

The National League and the American League, formed in 1876 and 1901 respectively, joined together under the National Agreement in 1903, making MLB the oldest major professional sports league in the United States and Canada. They stayed separate until 2000 when they merged under a single organization led by the commissioner of baseball. The first fully professional baseball team, the Cincinnati Red Stockings, began in 1869. Early years saw many league rivalries and players moving between teams freely until the 1903 agreement, which included the reserve clause that kept players tied to their teams.

MLB survived major challenges like the Black Sox Scandal of 1919, which involved a plan to fix the World Series, and later changes in leadership. It also endured the Great Depression and World War II without losing teams. After the war, Jackie Robinson broke baseball’s color barrier. The league expanded in the 1960s, adding new teams and starting an era of growth. Players later formed the Major League Baseball Players Association to negotiate better conditions, leading to free agency. The 1990s saw a rise in home runs, and reports in the mid-2000s revealed that many players used performance-enhancing substances.

Today, MLB is the third-wealthiest sports league in the world by revenue, after the National Football League and the National Basketball Association. Games are shown on TV, radio, and online across North America and other countries. In 2025, MLB attracted 71.4 million fans, the highest attendance of any sports league worldwide. MLB also oversees minor league teams, amateur leagues, and international tournaments like the World Baseball Classic. The New York Yankees hold the record for the most championships with 27, while the Los Angeles Dodgers were the reigning champions after winning the 2025 World Series against the Toronto Blue Jays.

History

Founding

In the 1860s, soldiers playing baseball during the Civil War helped the game grow across the country. This led to the formation of baseball's first governing body, the National Association of Base Ball Players. It started as an amateur league with over 400 clubs by 1867, mostly in the northeastern United States. Professional baseball began in 1869 with the first professional team, the Cincinnati Red Stockings.

The National Association of Professional Base Ball Players was formed in 1871, but it didn't last long. In 1876, the National League was created, focusing on teams rather than individual players. This new league made it easier to enforce player contracts and required teams to play all their scheduled games. The first National League game was played on April 22, 1876, in Philadelphia.

Dead-ball era

From 1900 to 1919, baseball was known as the "dead-ball era" because the balls used were not very lively, leading to low-scoring games. Pitchers like Walter Johnson and Cy Young dominated this time. Players used tricks to make the ball harder to hit, and home runs were rare. The rules also changed, making it harder for batters to score.

Rise in popularity

Baseball became more popular in the 1920s and 1930s. The New York Yankees started appearing in the World Series and won many games. Babe Ruth set a new home run record in 1927 with 60 home runs. However, the Great Depression in the 1930s made it hard for teams to make money, and they had to find new ways to attract fans.

World War II era

World War II caused many players to leave baseball to serve in the military. Teams had to use younger players and those not eligible for service. President Franklin D. Roosevelt supported keeping baseball going during the war, saying it was important for people's morale.

Breaking the color barrier

In the mid-1940s, Branch Rickey, from the Brooklyn Dodgers, worked to bring black players into major league baseball. Jackie Robinson became the first black player in 1947, breaking a long-standing barrier. He faced challenges but was welcomed by many and won the Rookie of the Year Award that year.

Women in baseball

Major League Baseball stopped signing women to contracts in 1952, but this rule was changed in 1992. Since then, no women have played in MLB.

Relocation and expansion

From the 1950s onward, baseball teams started moving to new cities. The Brooklyn Dodgers moved to Los Angeles in 1958, becoming the first West Coast team. Other teams followed, and new teams were added to both leagues in the 1960s and 1970s. This expansion helped baseball grow across the United States and into Canada.

Pitching dominance and rule changes

By the late 1960s, pitchers were dominating games. To balance this, rules were changed in 1969 to make it easier for batters. In 1973, the American League introduced a new rule to increase scoring.

New stadiums and artificial surfaces

In the 1960s and 1970s, many new stadiums were built, often with artificial turf because it was cheaper and easier to maintain. These changes affected how the game was played, with teams focusing more on speed and defense.

Scandals and a changing game

The 1980s brought changes and challenges to baseball. Players went on strike in 1981 and 1994, leading to many games being canceled. There were also issues with players using performance-enhancing drugs, which affected the game's fairness.

Steroid era, further expansion and near contraction

In the late 1990s and early 2000s, many players hit a lot of home runs, but some were using steroids. New teams were added in the 1990s, and there were plans to reduce the number of teams, but these were stopped.

The modern game

Today, baseball uses new technologies like Statcast to analyze games. These tools help players and teams improve. Rules have also changed to make games faster and more interesting, like banning extreme defensive shifts and introducing a pitch clock to speed up the game.

21st-century moves and potential expansion

In recent years, teams have moved to new cities, and there are discussions about adding more teams to MLB. The Oakland Athletics are moving to Las Vegas, and MLB is considering adding two new teams in the future.

Teams

See also: Timeline of Major League Baseball

Organizational structure

Major League Baseball (MLB) is guided by its constitution, first created in 1876. The commissioner leads MLB, overseeing important decisions and hiring officials for the games. MLB also manages marketing, labor, and television agreements. A special court decision in 1922 allowed MLB to have control over the sport, making it unique among sports leagues.

The current commissioner is Rob Manfred. MLB has several key executives who help run the league. MLB also has its own multimedia branch, MLB Advanced Media, which manages the official website and team websites. MLB Productions creates videos and broadcasts, and MLB Network provides sports coverage, with MLB owning most of it.

League organization

In 1920, a stronger leader called the commissioner was added to help make important decisions for all of professional baseball. Originally, there were eight teams in each league, the American League and the National League.

Over time, more teams joined. In the 1960s, eight new teams were added, including the first team outside the United States, the Montreal Expos. The 1970s saw the addition of the Seattle Mariners and the Toronto Blue Jays. By 1998, there were 30 teams in total, with new teams like the Arizona Diamondbacks and the Tampa Bay Rays.

Today, both leagues have the same rules, including using a designated hitter, which helps make the game fair for everyone.

Uniforms

A baseball uniform is special clothing worn by baseball players and some team leaders like field managers and coaches. Uniforms help show a person's job in the game and identify the team and its players through logos, colors, and numbers.

Traditionally, home uniforms show the team's name, while away uniforms show the team's city. But today, many teams use their name on both types of uniforms. Most teams also have special alternate uniforms, often using a different color. Throwback uniforms, which look like older styles, are also popular.

The first team to wear uniforms was the New York Knickerbockers in 1849. They wore blue pants, white flannel shirts (jerseys), and straw hats. Caps have always been part of baseball uniforms.

In the late 1880s, some teams started wearing striped uniforms. By the end of the 1800s, teams had two uniforms—one for home games and another for games at other teams' fields. By 1900, this was common in all major leagues.

Season structure

Spring training

Main article: Spring training

Spring training is a time for teams to practice and play exhibition games before the regular season starts. Teams hold training camps in Arizona and Florida, where the warm weather helps them practice without cold winter days. This time lets new players try out for spots on the team and gives everyone practice before real games begin. Teams in Arizona are called the Cactus League, and teams in Florida are called the Grapefruit League.

Spring training lasts about two months, starting in mid-February and ending just before the regular season begins in early April. Because pitchers need more time to get ready, they and the catchers start training a few days before the rest of the team.

Regular season

Each team plays 162 games during the season. Games are usually set up in groups of three against the same team, called a series. Sometimes, a series might have two or four games. All the games in a series are played at the same team’s home field. Teams often play several series in a row at home, then several on the road. Games are mostly played in the evening, but there are day games on special days like Opening Day and holidays. Sunday games are usually in the afternoon so teams can travel to their next game.

Teams play 13 games against each of the four teams in their own division. They also play six or seven games against teams in other divisions in their league and three games against teams in the other league. Each team has one special rival team from the other league that they play extra games against each year.

Since each league has 15 teams, two teams from each league play extra games together most days. From 2013 to 2022, teams played 20 of these extra games each season. Before 2013, these games were scheduled on certain weekends and periods during the season.

Starting in 2023, teams play at least one series against every other team each year. They play 13 games against division rivals, six or seven games against other teams in their league, and three games against teams in the other league, except for their special rival team.

Since 2022, teams compete for six spots in the playoffs each year. A team can get a spot by winning its division or by having one of the three best records among the non-division winners.

All-Star Game

The All-Star Game happens in early-to-mid July, right after the middle of the season. It is a special game where the best players from the American League and the National League play against each other. The game was first held in 1933 as part of the 1933 World's Fair in Chicago. Fans vote for some of the players to be in the starting lineup.

Postseason

See also: World Series and List of World Series champions

The regular season ends after the first Sunday in October, and then twelve teams start the postseason. These teams are the six division winners and six other teams with the best records. There are four rounds of games to decide the champion:

1. Wild Card Series, a best of three games between the lowest seeded division winner and three other teams.
2. American League Division Series and National League Division Series, each a best-of-five games.
3. American League Championship Series and National League Championship Series, each a best-of-seven games.
4. World Series, a best-of-seven games between the two league champions.

The team with the best regular-season record usually gets home-field advantage, meaning they get to play some games at their own field. This can help a team if the series goes to the last few games. The first two games of each series are played at the same team’s home field, which can give that team an early advantage.

International play

See also: List of Major League Baseball games played outside the United States and Canada, MLB Japan All-Star Series, MLB Taiwan All-Star Series, and 2019 MLB London Series

From 1986 to 2018, teams from Major League Baseball traveled to Japan for special games against top players from that country. These games helped share the love for baseball around the world.

MLB has also played games in China, Taiwan, Australia, Europe, and South Korea. These games aim to grow the popularity of baseball in new places. For example, in 2019, teams played in London, marking the first time MLB held regular-season games in Europe. In 2024, games were held in Seoul, South Korea, with special moments like a pitch thrown by Chan Ho Park, the first Korean-born player in MLB. MLB also supports international tournaments, such as the World Baseball Classic, where countries compete against each other.

Performance-enhancing drugs

See also: Doping in baseball and List of Major League Baseball players suspended for performance-enhancing drugs

In 1998, two famous baseball players, Mark McGwire and Sammy Sosa, hit more home runs than anyone before them. Another player, Barry Bonds, broke this record in 2001. There were questions about whether these players used special substances to improve their performance. McGwire later said he used a certain type of hormone that was allowed at the time.

In 2006, a book called Game of Shadows talked about many players possibly using these substances. A former leader of the U.S. Congress asked someone to look into this issue. The report showed that some players used a substance called HGH treatment for athletic enhancement, which was hard to detect in tests. In 2013, new rules were made to test players more often during the season and to find another banned substance called testosterone. Today, players can be suspended for many games or even for life if they break these rules. Some famous players, like Alex Rodriguez and Manny Ramirez, faced suspensions for using banned substances.

Media coverage

Television

See also: List of current Major League Baseball broadcasters

Linear

Starting in 2026, Fox, ESPN, NBC, TBS, and MLB Network will show MLB games on television in the United States. Fox has been the main TV partner for MLB since 1996. Since 2008, Fox has shown MLB games on Saturdays all season long. Fox also shows the All-Star Game each year and alternates showing the league championship games each year. Fox shows every game of the World Series.

ESPN has been MLB's cable TV partner since 1990. The network shows the weekly regular season game Sunday Night Baseball and postseason games of the Wild Card Series.

Before the 2026 season, MLB and ESPN ended their old deal early. NBC will show Sunday Night Baseball and the Wild Card games for now, while ESPN will show midweek games on its TV channels.

TBS began showing Sunday afternoon regular season games nationwide in 2008, which changed to Tuesday night games in 2022. From 2007 to 2020, TBS had exclusive rights to any tiebreaker games that decided division or wild card champions. It also shows the Division Series round of the playoffs. TBS shows the league championship series that Fox does not, showing the NLCS in odd-numbered years and the ALCS in even-numbered years.

In January 2009, MLB started MLB Network, which shows news and coverage from around the league and airs 26 live games in the 2009 season. Each team also has local broadcasts for all games not shown nationally. These games are usually split between a local TV station and a local or regional sports network (RSN), though some teams only show local games through RSNs or their own team networks.

Since Canada only has one team, Sportsnet shows Toronto Blue Jays games nationwide. The channel is owned by Rogers Communications, which also owns the Blue Jays. Sportsnet also shows Fox's Saturday afternoon games, the All-Star Game, playoff games, and the World Series. In April 2011, TSN2 began showing ESPN Sunday Night Baseball in Canada. TVA Sports shows Blue Jays games in French.

Streaming

Several MLB games are shown only on streaming television. After a year of exclusive games on Facebook, MLB worked with YouTube to stream weekly games from the 2019 season until 2022. In 2022, MLB made a deal with Apple Inc. to launch Friday Night Baseball on its Apple TV+ streaming service, and NBC Sports to show MLB Sunday Leadoff on Peacock.

Since the 2023 season's Division Series, HBO Max has shown games broadcast by its sister network TBS (both owned by Warner Bros. Discovery).

In the 2024 season, The Roku Channel began streaming MLB Sunday Leadoff. Midway through that season, it was confirmed that TelevisaUnivision had signed a multi-year deal to broadcast MLB En Vivo on Tuesdays on UniMás, TUDN and ViX, with live clips and highlights of up to 15 games each week. The deal also included exclusive Spanish-language TV rights to the 2024 American League postseason games (ALDS and ALCS) with select games on Univision as well as UniMás, TUDN and Vix, and Game 1 of that season's World Series, sharing airtime with Fox and Fox Deportes.

Announced in November 2025, MLB signed three-year media-rights deals with Netflix, ESPN, and NBCUniversal for the 2026 to 2028 seasons. For the 2026 season, Peacock will again show MLB Sunday Leadoff, while Netflix will stream multiple events each year, including the Home Run Derby (taking over from ESPN), one game on Opening Night of the season, and a special-event game each year, starting with MLB at Field of Dreams in 2026.

Blackout policy

See also: Syndication exclusivity

MLB has several blackout rules. A local broadcaster has first right to show games of the team in their area over national broadcasters if the game is not exclusive to the national broadcaster. A market that has a local team playing in a non-exclusive game will see an alternative feed on the national broadcaster. MLB's streaming service is also subject to the same blackout rules. Commissioner Robert Manfred has said he wants to change the blackout policy to make streaming rules looser.

Radio and Internet

The first baseball game ever broadcast on radio was a Pittsburgh Pirates versus Philadelphia Phillies game on August 5, 1921. The game was broadcast by KDKA of Pittsburgh, and the Pirates won 8–5. It was broadcast by KDKA staff announcer Harold Arlin. That year, KDKA and WJZ of Newark broadcast the first World Series on the radio, between the New York Giants and the New York Yankees, with Grantland Rice and Tommy Cowan calling the games for KDKA and WJZ, respectively. However, the broadcasters were not at the game, but gave reports from a telegraph wire. In 1922, WJZ broadcast the entire series, with Rice doing play-by-play. For the 1923 World Series, Rice was joined on Westinghouse for the first time by Graham McNamee.

During the 1923 World Series, Rice was the main broadcaster, but during the fourth inning of Game 3, he passed the microphone to McNamee. This was the start of McNamee's career, and McNamee became the first color commentator. Although often criticized for his lack of expertise, McNamee helped make baseball more popular.

In (/wiki/1998_in_baseball), national radio broadcasts moved to ESPN Radio. ESPN Radio currently broadcasts Sunday Night Baseball games during the regular season, as well as Saturday and occasional weekday games, along with the All-Star Game and all postseason contests. Since 2021, TUDN Radio airs Spanish-language coverage of select regular season and postseason games, including the World Series.

In addition, each team has its own announcers, who broadcast during the regular season. Most teams have regional networks to reach their fans; some of these networks (such as the New York Yankees Radio Network) reach across the United States. Major League Baseball has an exclusive deal with XM Satellite Radio, which includes the channel MLB Network Radio and live play-by-play of all games.

MLB games are also broadcast live on the internet. All TV and radio broadcasts of games are available by subscription to MLB.tv at Major League Baseball's website, MLB.com, and radio-only broadcasts are also available by subscription to MLB.com Gameday Audio. In 2026, MLB.tv will be integrated into the ESPN App.

Since 2005, Major League Baseball has partnered with XM Satellite Radio, launching a 24-7 channel, MLB Home Plate (now MLB Network Radio) which carries every major league game. Games are also carried on MLB Gameday Audio.

While all teams have a network of stations carrying their games in English, many teams also broadcast their games in Spanish, on a second network. In addition, when the Washington Nationals were based in Montreal as the Montreal Expos, their games were broadcast in both English and French. Some Toronto Blue Jays games have been broadcast in French as well. Selected games of the Los Angeles Dodgers are broadcast in Korean by KMPC.

Financial landscape

In recent years, teams have relied more on local cable TV rights fees, which became unstable in the 2020s and which are not shared equally among teams. Following the Disney-Fox merger, Disney sold Fox's regional broadcasting networks, which covered 14 of MLB's 30 teams, to Diamond Sports Network / Bally Sports. Diamond filed for bankruptcy in 2023 and used bankruptcy rules to cancel or change its TV deals with a third of the league. Teams that had locked in stable deals near the peak of the market are now in a stronger financial position than the average team. Critics say that industry revenues and team values are still rising.

International broadcasting

Disney Media Networks Latin America through its channels (ESPN, ESPN Caribbean, ESPN Brazil) and Disney+ owns the rights to more than 180 regular season games (at least 1 game per day), the Home Run Derby, the All Star Game and the postseason including: the Wild Card Series, the Division Series, the Championship Series and the World Series for all of Latin America and the Caribbean. ESPN broadcasts some MLB games in other countries, including ESPN Australia in Australia and New Zealand, ESPN Africa, and ESPN in the Netherlands.

In Mexico, until 2022, Fox Sports aired five regular season games per week and postseason games that belong to the league that broadcasts its American counterpart (including the Wild Card Series). Likewise, TUDN carried 4 matches a week until 2022: through pay TV, games were shown on Tuesdays and Thursdays, while on Saturdays (generally at 12:00 p.m.) and Sundays (rotating between NBA games, until the start of the NFL season) games were shown on Canal 9. Starting with the Championship Series, it only showed one division and the whole World Series, these were shown on free-to-air TV for 59 years. Starting with the 2023 season, Imagen Televisión announced it would begin broadcasting a regular season game every Saturday and Sunday as well as the playoffs and the World Series on open television and its website in Mexico.

In Argentina, Fox Sports carries 5 regular season games per week and postseason games that belong to the league that broadcasts its American counterpart (including the Wild Card Series).

In Venezuela, since the 2016 season the cable channel IVC has the broadcast rights, they currently air 7 games per week. Starting with the 2022 season, Televen broadcasts two games a week and the postseason on free-to-air TV While Venevisión, starting with the 2023 season, would return with the space "El Juego de la Semana" that carries a game every Sunday and non-working days on free-to-air television.

In the Dominican Republic since 2009 Grupo Altice has broadcast the entire regular season, playoffs and World Series through pay TV while on free-to-air TV and radio Grupo Corripio airs 7 games per week and the entire postseason.

In Spain, Movistar Plus+ has the rights to broadcast the entire season, including one game daily, and the postseason, covering all games in the championship series and World Series.

Channel 5 in the United Kingdom previously showed MLB games, including the All-Star Game and postseason games, on Sunday and Wednesday, usually starting at 1 a.m. BST. Most recently, Johnny Gould and Josh Chetwynd presented MLB on Five on that station. The channel covered baseball beginning on its opening night in 1997, but for financial reasons, it decided not to show MLB for the 2009 season. BT Sport ESPN shows live and recorded games several times a week—it is available with BT Sport and (on a subscriber-basis) Virgin Media in the UK. ESPN America televised many games in the UK and dozens of other countries; in May 2013, ESPN announced that it would shut down the channel on July 31, 2013.

In the Middle East, North Africa and France, MLB games are broadcast on beIN Sports channels.

In Germany, Austria and Switzerland, as many as 500 MLB games will be broadcast from 2022 exclusively on the Sport1 platforms until 2026. Sport1 also broadcasts MLB games in Hungary, as of 2025.