Carpenter himself says it's the former. So does manager Tony La Russa. It will need to be, because Peavy is one of the few pitchers in the National League who can match Carpenter pitch-for-pitch.
From mid-May until early September, Carpenter was simply the best pitcher in the NL. He went from June 8 until Sept. 23 without a loss. He enjoyed a run of 16 consecutive starts in which he and the team were unbeaten every time, he pitched at least seven innings every time and he never allowed more than three earned runs. It was the definition of dominance.
Then he hit the end of the season, and he slowed. It was natural to wonder whether the right-hander, who tallied 241 2/3 innings, was fatigued. But he pointed to something else: the otherworldly concentration that marked so much of his season finally flagged a little bit. With the division title in hand, Carpenter let a little bit of his fantastic focus fade.
"I was so locked in for the whole season, and we clinched, and there were some other things going on," Carpenter said. "You start looking ahead. [I was] concerned with keeping myself fresh and staying healthy to get me to the end of the season to have the opportunity to be here [in the playoffs]. And you lose that little edge.
"I felt that my last start, that edge was back. I felt like I pitched well. The results weren't what I was looking for, but I felt like my stuff was back. My stuff was good. And I'm really looking forward to [Game 1]."
Carpenter is the ace the Cardinals didn't have in the 2004 playoffs, when they made the World Series before being swept by the Red Sox. He missed the entire '04 postseason with a rare nerve ailment in his right arm. It's no secret that St. Louis' chances of a repeat pennant, and perhaps its first world title in 23 years, depend heavily on Carpenter's performance.
La Russa has little doubt that with the stakes raised, Carpenter's performance will ratchet up to match.
"I think if you look at virtually every starter, we've had some rough starts here in the last two weeks, and I just think they're not selfish enough," La Russa said. "They were pitching to help us win, we clinched it and they lost an edge.
"Physically we're in real good shape, and the big key is to get back on it mentally and understand that if we don't pitch, we don't win. Against the pitching we're going to face in the postseason, you're not going to outscore people."
Matthew Leach is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.