Choo, who was hitting .244, is returning nearly two weeks early after undergoing surgery for a broken left thumb on June 28. He was expected to be out eight to 10 weeks.
"So far, he hasn't shown any issue with anything," Indians manager Manny Acta told reporters. "Right now, it's about timing and reacting to pitches inside if he gets jammed, if it hurts him or not."
The Indians trail the Detroit Tigers by three games in the American League Central Division.
(Reporting by Gene Cherry in Raleigh, North Carolina; Editing by Steve Ginsburg; To query or comment on this story email firstname.lastname@example.org)