The win put Cleveland back at .500, after dropping below that mark for the first time since April on Sunday.
Justin Masterson (7-8) picked up the win, giving up only one earned run in 7 1/3 innings. He allowed seven hits and struck out six.
The Indians opened the scoring in the third inning when Shin-Soo Choo hit a two-run shot off Tommy Hunter (4-5).
Baltimore's Omar Quintanilla made it 2-1 with an RBI-double in the fifth.
Michael Brantley's RBI-single in the eighth made it 3-1 and that's how it stayed. Chris Perez pitched the ninth and recorded his 27th save of the season.
The Indians will begin a three-game home set against Detroit on Tuesday at 7:05 p.m. ET.
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