Following the Cardinals' 7-6 win over the Cubs, Matheny explained that the decision to make the switch had little to do with Berkman ailing and more because he wanted to find at-bats for Freese.
"Early on, when I got here this morning, I was still trying to figure out if we could get [Freese] in," said Matheny, whose first lineup had Berkman playing first and Carpenter starting at third. "I made the late scratch to get David in and to give Lance a day on a pitcher he's had a little bit of a tough time with."
Berkman entered the day 7-for-34 against Cubs starter Paul Maholm.
The Cardinals have been prepared to liberally insert time off for Berkman, who just came off the disabled list on Sunday. He missed more than three weeks nursing a left calf strain. Berkman confirmed on Monday that he has had no recent recurrence of discomfort in his leg.
"I feel good," he said. "I'm ready to play. Part of being a veteran guy and putting up numbers to help the team is just being available to play every day. I feel very comfortable and confident that I can do that, particularly now that I have this calf thing out of the way."
Berkman started on both Sunday and Monday, going 3-for-9 with one RBI.
Carpenter, who was initially slated to start at third base, moved across the diamond to take Berkman's spot. He delivered a key solo homer for the team in the eighth inning. Freese was inserted to play third and bat fifth. He finished 0-for-5.
Freese is hitless in his last 16 at-bats and has grounded into four double plays during that span. His batting average has dropped to a season-low .272.
"He's been hitting some balls hard and not getting anything to go, and now he's fighting himself," Matheny said. "He just has to stop and breathe a little bit. That's part of the reason why I wanted to give him a day [off]. But some guys just can't wait to get back in there. Today was one of those days for David.
"We just needed to keep pointing out the positives. He's hitting some balls hard. It's just a tough time for him right now."