The Seattle Mariners franchise has retired two numbers, which are displayed on the façade above center field at T-Mobile Park. They hang alongside Jackie Robinson's Number 42, which was retired by all Major League teams in 1997.
11 - Edgar Martinez
- Edgar Martinez retired at the conclusion of the 2004 season having spent his entire 18-year Major League career with the Mariners. He finished with a .312 lifetime batting average, .418 on-base percentage and a .515 slugging percentage (.933 OPS).
- He was inducted into the Mariners Hall of Fame on June 2, 2007, andhis number 11 was retired by the Mariners on August 12, 2017.
- On July 12, 2019, Edgar was inducted into the National Baseball Hall of Fame in Cooperstown on July 22.
- Over his career, he made seven All-Star appearances, won a pair of batting titles, five Silver Slugger Awards and five Outstanding Designated Hitter of the Year Awards. Upon his retirement, Major League Baseball renamed the Outstanding Designated Hitter Award the “Edgar Martinez Award.”
- Edgar remains the franchise's all-time leader in doubles, runs, RBI, walks, extra-base hits and games played.
24 - Ken Griffey Jr.
- Ken Griffey Jr. retired during the 2010 season, having spent 13 seasons of his outstanding 22-year career with the Mariners. He finished with 630 home runs, currently ranked seventh all-time.
- On August 6, 2016, Ken’s number 24 became the first-ever retired by the Mariners. Number 24 is also retired throughout the Mariners entire minor league system.
- Griffey and Mike Piazza were inducted into the National Baseball Hall of Fame in Cooperstown on July 24, 2016, becoming the 311th and 312th members.
- Griffey, in his first year on the Baseball Writers' Association of America ballot, was named on 437 of 440 ballots by voting members of the BBWAA, setting a new record with 99.3% of the votes (since topped by Mariano Rivera and Derek Jeter) .
- Over his Major League career, Junior made 13 All-Star Game appearances, won four AL home titles, seven Silver Slugger and 10 Gold Glove Awards, and was the 1997 AL Most Valuable Player.
42 - Jackie Robinson
- In 1947, Jackie Robinson became the first African-American to play in the Major Leagues. He played for Brooklyn Dodgers from 1947-56,
- His number 42 was retired by Major League Baseball in 1997.
- Jackie was inducted into the National Baseball Hall of Fame in 1962. His plaque reads: "Leading NL batter in 1949. Holds fielding mark for second baseman playing in 150 or more games with .992. Led NL in stolen bases in 1947 and 1949. Most Valuable Player in 1949. Lifetime batting average .311. Joint record holder for most double plays by second baseman, 137 in 1951. Led second baseman in double plays 1949-52."