The Athletics (often referred to as the A's) are an American professional baseball team based in West Sacramento, California. The Athletics compete in Major League Baseball (MLB) as a member club of the American League (AL) West Division. The team will play its home games at Sutter Health Park in West Sacramento for the 2025–2027 seasons before its planned relocation to the Las Vegas metropolitan area. While in West Sacramento, the team is being referred to as simply the "Athletics" and "A's", with no city name attached. The franchise's nine World Series championships, fifteen pennants, and seventeen division titles are the second most in the AL after the New York Yankees. One of the AL's eight charter franchises, the team was founded in Philadelphia in 1901 as the Philadelphia Athletics. They won three World Series championships in 1910, 1911, and 1913, and back-to-back titles in 1929 and 1930. The team's owner and manager for its first 50 years was Connie Mack, and Hall of Fame players included Chief Bender, Frank "Home Run" Baker, Jimmie Foxx, and Lefty Grove. The team left Philadelphia for Kansas City, Missouri, in 1955 and became the Kansas City Athletics, before moving to Oakland, California, in 1968 and becoming the Oakland Athletics. The Athletics played their home games at the Oakland Coliseum from 1968 until 2024. Nicknamed the "Swingin' A's", under owner Charlie O. Finley they won three consecutive World Series in 1972, 1973, and 1974, led by players including Vida Blue, Catfish Hunter, Reggie Jackson, and Rollie Fingers. After being sold by Finley to Walter A. Haas Jr., the team won three consecutive pennants and the 1989 World Series behind the "Bash Brothers", Jose Canseco and Mark McGwire, as well as Hall of Famers Dennis Eckersley, Rickey Henderson and manager Tony La Russa. In 2002, the Athletics set a then American League record for most consecutive wins in a season with twenty, an event that would go on to be the pioneering step in the application of sabermetrics in baseball. The streak record was later broken in 2017 by the Cleveland Indians. From 1901 through the end of 2024, the franchise's overall win–loss record is 9,329–9,859–87 (.486).

Sutter Health Park

The Tampa Bay Rays are an American professional baseball team based in St. Petersburg, Florida. The Rays compete in Major League Baseball (MLB) as a member club of the American League (AL) East division. Since its inception, the team's home venue has been Tropicana Field. Following nearly three decades of unsuccessfully trying to gain an expansion franchise or enticing existing teams to relocate to the Tampa Bay area, an ownership group led by Vince Naimoli was approved on March 9, 1995. The team began play as the Tampa Bay Devil Rays in the 1998 Major League Baseball season. The team's first decade of play was marked by futility; they finished in last place in the AL East in all but the 2004 season, when they finished second to last. Following the 2007 season, Stuart Sternberg, who had purchased controlling interest in the team from Vince Naimoli two years earlier, changed the team's name from "Devil Rays" to "Rays", now meaning both a manta ray and a ray of sunshine; a manta ray logo appears on the uniform sleeves while a sunburst appears on the uniform front. The 2008 season saw the Rays post their first winning season, their first AL East championship, and their first American League pennant (defeating the rival Boston Red Sox in the ALCS), though they lost to the Philadelphia Phillies in that year's World Series. Since then, the Rays have played in the postseason seven more times, winning the American League pennant again in 2020 and losing to the Los Angeles Dodgers in that year's World Series. The Tampa Bay Rays' chief rivals are the Boston Red Sox and the New York Yankees, which also play in the AL East. Regarding the former, there have been several notable on-field incidents. The Rays also have an in-state interleague rivalry with the National League (NL)'s Miami Marlins (originally the Florida Marlins), whom they play in the Citrus Series. Through 2022, the Rays' all-time record is 1,912–2,034 (.485).