Adrian Beltre hit two RBI singles, Mike Morse and Richie Sexson hit sacrifice flies, and Ichiro Suzuki had two runs and two hits for the Mariners (64-71), who have seven wins in their last 10 contests.
Cha (2-0) walked one batter and struck out four.
J.J. Putz earned his 29th save.
Rocco Baldelli, Ben Zobrist and Delmon Young all belted solo home runs; while Zobrist, Carl Crawford and Greg Norton each had two hits for the Devil Rays (54-82), who have dropped seven of their last 10 games.
Losing pitcher J.P. Howell (0-2) surrendered three runs and eight hits in 6 2/3 innings with three walks and five strikeouts.