The 2005 NL Cy Young Award winner threw 40 pitches Sunday, two days after throwing off a mound for the first time in two weeks.
Carpenter threw two sets of 20 pitches with a couple of minutes rest in between. He has been limited since March 3 because of a bulging disk in his neck.
"I was excited to get back out there and throw a little bit," Carpenter said. "Now we move on to the next step. I think if I wake up good enough tomorrow we can go out and do that again maybe sometime soon."
Carpenter had been slated to start for St. Louis in the April 4 major league opener at Miami. It's unclear when he will pitch in a spring training game.
"I'm not going to look ahead," he said.
St. Louis had planned to limit his spring training innings after he pitched a major league-high 273 1/3 last year, including the postseason.