The Cleveland Indians placed Mike Clevinger on the 10-day injured list with a back injury and manager Terry Francona told reporters that the right-hander won't be able to pick up a ball for six-to-eight weeks.
The Indians said Clevinger has a teres major muscle strain in his right upper back. The move was made retroactive to Monday. Right-hander Nick Wittgren was recalled from Triple-A Columbus in a corresponding move.
Francona told reporters it's a "significant" injury.
Clevinger left his start on Sunday against the Toronto Blue Jays after five innings because of upper back tightness.
Clevinger had 10 strikeouts over five scoreless innings and is off to an outstanding start this season, throwing 12 scoreless innings with 22 strikeouts over his first two outings.
He was 13-8 with a 3.02 ERA in 32 starts last season, pitching a career-high 200 innings and striking out 207 batters.