"Reds third baseman Scott Rolen missed his second start in three games Thursday, and manager Dusty Baker was cryptic as to why.

"He's very sore," Baker said. "He's been tight for a couple of weeks."

Rolen was available to pinch-hit. He's batting .419 with two home runs and 10 RBI over his past nine games.

His absence loomed large. Miguel Cairo, who started in his place, made an error on a potential double-play ball in the ninth inning of the 10-9 loss to Atlanta. If Cairo had made the play, it's likely the Reds would have won.

The Reds are going to be cautious with Rolen. It was the second time in a row he's been out of the lineup for a day game after a night game.

"We're a different lineup without him," Baker said.

The Reds don't have a replacement ready at Triple-A Louisville if Rolen goes on the disabled list. Juan Francisco is out for three or four more weeks after an appendectomy and Todd Frazier, who started at third for the Bats Wednesday, is hitting .186.

CHAPMAN UPDATE: Pitching prospect Aroldis Chapman might not even miss a start because of the blister that forced him out of Louisville's game Wednesday.

Reds general manager Walt Jocketty got a report from Bats trainer Tomas Vera.

"Tomas said it's a blister over a callus," Jocketty said. "They'll know more Saturday when he throws his bullpen. He might miss a start, but it's nothing serious."

Chapman pitched 51/3 shutout innings Wednesday and allowed three hits, walked three and struck out seven in the Bats' 4-2 win over the Lehigh Valley IronPigs. He was coming off a start in which he allowed eight runs over 31/3 innings in a 14-3 loss at Rochester, but that start did not worry the Reds."