The Cardinals could lose ace pitcher Chris Carpenter for the rest of the month. Carpenter has been placed on the 15-day disabled list with arthritis in his right elbow. No exact timetable has been made for Carpenter’s return.

Carpenter experienced swelling in the elbow after a bullpen session in Houston on Sunday. He left the team immediately and was made unavailable for tonight’s scheduled start.

"There is going to be no pressure for him to get back before he’s ready," manager Tony LaRussa said. "So whenever he’s ready – next month – I don’t know."

The Redbirds called up 31-year-old Randy Keisler to replace Carpenter in the rotation. His last major league start came back in 2005 with the Cincinnati Reds.

"He throws the ball over the plate," pitching coach Dave Duncan said. "He’s got some experience. He gave me the impression he’s certainly not afraid."