Ramos tore his ACL and MCL in the seventh inning of Cleveland's win over the Boston Red Sox on Sunday. He fielded a weak hit in front of the plate and was throwing to second base when his left knee buckled and he crumpled to the infield grass.
Ramos, 34, played in 44 games this season -- nine with Cleveland, 35 with Detroit. He batted .226 with two homers and seven RBIs for the Indians, who have been without Gold Glove catcher Roberto Perez for much of the year.
Perez was placed on the injured list this month with right shoulder inflammation and back spasms. He spent 60 days on the IL earlier this season after undergoing surgery on his right middle finger, which was broken in April when reliever James Karinchak crossed him up on a pitch against the Chicago White Sox.
Austin Hedges has handled most of Cleveland's catching duties this season.
Ramos drove in two runs Sunday. After he got hurt, Hedges replaced him and hit a score-tying home run.