Corey Kluber has a nondisplaced fracture of his right ulna after he was hit on the arm by a line drive on Wednesday night.
The line drive came off the bat of Miami Marlins outfielder Brian Anderson.
Kluber's arm was placed in a cast, and he'll be re-evaluated in Cleveland on Thursday.
He has a 5.80 ERA and 38 strikeouts in 35.2 innings this season.