BOSTON -- The Cardinals are dealing without three injured regulars as they begin a three-city Interleague trip: Albert Pujols, Yadier Molina and Cesar Izturis. They got news on all three Saturday, and the reports were good, bad and uncertain, respectively.

Thanks to the series of injuries, meanwhile, the Redbirds prepared to make a roster move. Carrying only 12 hitters in the first place, and with Molina and Izturis both at least limited if not entirely unavailable, the club made preparations to call up outfielder Nick Stavinoha as an extra warm body for the next few days.

Manager Tony La Russa said Saturday that Pujols, who has been on the disabled list since June 11 due to a strained left calf, will join the team for workouts beginning Tuesday in Detroit. It now appears to be a very real possibility that Pujols could be activated the first day he is eligible, which would be Thursday's series finale at Comerica Park.

"I think he's feeling really good," La Russa said.

Molina, on the other hand, took a small step backwards on Saturday. The Cards catcher, recuperating from a concussion he sustained on June 15, was held out of the lineup due to a regression in his performance on the imPACT concussion screening exam.

Molina started at designated hitter on Friday night and hit a home run. He said he did not feel any different on Saturday than he did on Friday, but because of the screening results, he was not cleared to play. The Cardinals considered him able to pinch-hit and possibly to play the field in an emergency, but not to start at catcher.

"He didn't score as well today as he did last night," La Russa said. "It could have been the stress of playing. We figured we were best just to give him the whole day off."

Molina simply said he felt the same on Saturday as on Friday.

Meanwhile, the club was still awaiting news on Izturis, a day after he sustained a right hamstring strain. The shortstop met with George Paletta, the Cardinals' head team physician, at the team hotel on Saturday afternoon.

While the Cardinals waited for a verdict on the severity of Izturis' injury, they also pondered a roster move. Stavinoha, rather than a middle infielder, is likely to be brought up from Triple-A Memphis in time for Sunday's game.