ST. LOUIS -- Cardinals pitcher Chris Carpenter is feeling optimistic about his on-and-off rehab program after he threw an extended bullpen session on Friday.
After four simulated innings and 106 pitches counting warm-ups, the 38-year-old Carpenter said it was the best he had thrown and something he could build on. The next step likely will be facing hitters.
"It definitely was the best throw I've had so far," Carpenter said. "At some point, I'm going to have to start facing hitters again and get going."
He added, "After today, I think we've got a pretty good shot."
Carpenter has been happy with his past two sessions after a "so-so" outing Sunday.
Manager Mike Matheny thought Carpenter was as strong at the finish as he was at the beginning, with good late life and movement, but was circumspect about the next test.
"You could see his stamina's there and he's in terrific shape," Matheny said. "As far as what's next, we've got a plan, I just don't have it memorized."
The 2005 NL Cy Young Award winner and longtime Cardinals ace was sidelined before spring training by a nerve injury that causes numbness and tingling on the right side of his body. Lately he's been dealing with a lower-back injury that began bothering him several months ago but he said was not a herniated disk.
"It's been a concern," Carpenter said. "Any sign that it starts getting out of whack, we make sure we back off, make sure we control it, before it does turn into something severe."
The often-injured Carpenter pitched sparingly last season after undergoing radical surgery to relieve nerve compression.