Here is a comprehensive summary of the Seattle Mariners:

The Seattle Mariners are a professional baseball team in MLB's American League West, created in 1977 as an expansion franchise after a lawsuit following the Seattle Pilots' relocation to Milwaukee; they played in the Kingdome before moving to T-Mobile Park in 1999. After struggling for over a decade, the team found its stride in the 1990s with Hall of Famers Ken Griffey Jr., Randy Johnson, and Edgar Martínez, who delivered an iconic walk-off double in 1995 to clinch their first playoff series win against the Yankees. In 2001, bolstered by rookie sensation Ichiro Suzuki, the Mariners set an American League record with 116 regular-season wins, though they failed to reach the World Series. Following that peak, the franchise endured a two-decade playoff drought, finally returning to the postseason in 2022 and winning their first AL West title since 2001 in 2025. As of the end of the 2025 season, they hold an all-time record of 3,689–4,022–2 (.478), and they remain the only active MLB franchise never to have appeared in the World Series, holding the sport's longest active championship drought.