Manager Manny Acta said before Tuesday's series opener against first-place Detroit that Sizemore, sidelined since July 18 with a bruised right knee and after undergoing surgery for a sports hernia, will definitely not be back this month. The Indians originally said Sizemore would be out 4 to 6 weeks, placing his return around Sept. 1. Acta would not give a possible date for the 28-year-old's return.

"We never anticipated him coming back by the end of this month," Acta said.

Sizemore has not resumed baseball activities. Acta said there's a chance that by the end of the week he could be playing catch and taking swings.

A three-time All-Star, Sizemore's career has been slowed by injuries the past few seasons. He played only 33 games last year before having microfracture surgery on his left knee. Sizemore worked his way back - ahead of schedule - and played well earlier this season before bruising his right knee sliding into second base on May 10. He then aggravated the knee while running out a double last month.

Sizemore had an operation to fix the hernia in Philadelphia on July 21.

Acta was asked if Sizemore could be a major contributor when he does come back.

"Who knows?" he said.

The Indians, who trail the Tigers by four games in the AL Central, are hoping to get outfielder Shin-Soo Choo back for the playoff chase. He's been on the DL since June 25 with a broken left thumb. Choo began a rehab assignment on Monday at Lake County (A). Acta said the plan is for Choo to steadily work his way up the minor-league ladder for a week, facing better pitching along the way, before rejoining Cleveland.

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