CLEVELAND -- When Travis Hafner went on the 15-day disabled list with right shoulder soreness on April 29, the Indians hoped he'd be ready to return by the time he was eligible to come off the DL on May 14.
Nearly four weeks later, Hafner is still not ready to rejoin the Tribe. His rehab assignment at Triple-A Columbus has been briefly interrupted by mid-back tightness he felt after three at-bats Sunday.
But head athletic trainer Lonnie Soloff said the setback is not serious and that Hafner should be ready to resume his rehab by the end of the week after taking batting practice at Progressive Field on Tuesday and Wednesday.
"He has a history of mid-back tightness during games," Soloff said. "He'll receive treatment over the next 48 hours."
As for the surgically repaired shoulder, Hafner has reportedly responded well to treatment and the game activities with Columbus. Sunday's game was his third in four days, and Pronk said the shoulder was asymptomatic. The Indians are not saying when they expect Hafner to return to the big leagues, but he's 10 days into a rehab assignment that can last up to 20.
"Everything's been feeling good," Hafner said. "I think they want to see me play a certain number of games in a row to make sure I'm ready to play five or six games a week."
The doctors told Hafner the shoulder soreness he felt in April was natural, considering he was just six months removed from arthroscopic surgery, and the cold weather might have contributed to it. But Hafner was still surprised when his shoulder went weak late in the month.
"I wasn't expecting any problems at all," he said. "I definitely wasn't expecting it when it happened."
The injury interrupted a positive return for Hafner, who was batting .270 with four homers and eight RBIs in 17 games. Thus far in his rehab, he's batting .455 (10-for-22) with a homer, two doubles and five RBIs in six games.
"I feel I can go out now and be comfortable playing," Hafner said. "My swing's feeling really good. I'll be excited to get up here and play."
Anthony Castrovince is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.