The 1983 Major League Baseball season was the seventh season in the history of the Seattle Mariners. They were seventh in the American League West at .370, 39 games behind, with the worst record in the major leagues. They became the first team to fail to sweep an opponent in any series. In his third season as the Mariners' manager, Rene Lachemann was fired on June 25, succeeded by Del Crandall. At the time, the Mariners were .350, on an eight-game losing streak, and had the worst record in the majors. A former major league manager, Crandall was managing the Triple-A Albuquerque Dukes, the Pacific Coast League affiliate of the Los Angeles Dodgers.

Offseason

Regular season

Season standings

Record vs. opponents

Notable transactions

Roster

Player stats

Batting

Starters by position

''Note: Pos = Position; G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Other batters

''Note: G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Pitching

Starting pitchers

Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Other pitchers

Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Relief pitchers

Note: G = Games pitched; W = Wins; L = Losses; SV = Saves; ERA = Earned run average; SO = Strikeouts

Farm system