A year later it was Carpenter who, due to numbness and discomfort in his right shoulder, neck and back, had to be shut down. He wouldn't return until mid-September, leaving him with enough time to make only three regular-season starts.
Carpenter had a recurrence of those symptoms last week, prompting him to inform the Cardinals that he cannot continue to pitch. He's unlikely to pitch in 2013.
As a result, it leaves the Cardinals facing the prospect of moving on without one of their aces for the third straight season.
"Adversity is a part of your success," Mozeliak said on Tuesday. "The best thing you can do is have contingency plans and have depth. The one good thing about this system now is it's strong, it's healthy and we have a lot of talent coming. When you get over the pity party of not having someone, you have to move on."
That talent -- and indeed, there seems to be plenty of it -- will just have to step up a little earlier than anticipated.
For those who have clamored for the Cardinals to be more active this offseason, it could turn out that the organization will profit from its inactivity. That's because Mozeliak, despite overtures from several interested trade partners, decided to keep his group of young pitching intact. His reasoning was based on those pitchers' long-term potential, yes, but also with a hesitancy to dip into depth that could be critical in the immediate future.
The Cardinals knew they would enter Spring Training with questions about Carpenter and Jaime Garcia, both of whom dealt with serious injuries in 2012. While the club was optimistic that both starters would arrive in Jupiter, Fla., healthy, there was always some caution in making plans under the ideal scenario.
And so Mozeliak held onto Lance Lynn and Shelby Miller and Joe Kelly and Trevor Rosenthal. Now, the Cardinals need at least one, and possibly two, to help stabilize a rotation sans Carpenter.
"Right now, both [manager] Mike [Matheny] and I feel pretty good about the arms we have coming into camp," Mozeliak said. "At some point, you're going to have to find out if they can do it or not anyway. We really believe this group is looking forward to this challenge."
All four of the young right-handers had been told to prepare as starters this spring in case they were to be needed in the rotation. Even before Carpenter shut down, the Cardinals had planned to fill the fifth rotation spot with one of the young arms.
Lynn, who filled Carpenter's void in the rotation last year, was seen as the favorite for that job. He is coming off an 18-win season in which he was also an All-Star.
Assuming Lynn is a near-certainty for the rotation given the latest news, the Cardinals will spend the spring evaluating their other options. Miller, Kelly and Rosenthal each made their Major League debuts in 2012 and all three pitched well enough to be included on the club's postseason rosters.
Kelly has the most Major League starting experience of the three, having come up to St. Louis in June to fill in when Garcia was moved to the disabled list. In 16 starts, Kelly went 4-6 with a 3.74 ERA.
Rosenthal made 19 regular-season appearances out of the bullpen and then shined on the postseason stage, where he regularly hit triple digits on the radar gun. He did not allow a run in seven playoff appearances.
Miller, after working through his first bit of professional adversity, earned a callup in September. He pitched mainly out of the bullpen but did impress when given the chance to start on the final day of the regular season. He shut out the Reds in a six-inning start.
"We have some arms that have proven what they can do out of the 'pen," Matheny said, "We're anxious to see what they do with the opportunities we give them to start during the spring."
The Cardinals, in filling that rotation opening, could go another direction, of course, which would be to find help from outside the organization. Though the free-agent market has largely dried up, one particularly intriguing name remains: Kyle Lohse.
Lohse turned down the Cardinals' $13.3 million qualifying offer in November to test the market but, presumably because he will cost the club that signs him an early Draft pick, he has not garnered the level of interest that he anticipated. Lohse is coming off a season in which he went 16-3 with a 2.86 ERA for the Cardinals.
The Cardinals, aside from making the qualifying offer in order to secure Draft compensation, never made a serious run at re-signing Lohse this winter. The team's depth made such a courting unnecessary.
But now that circumstances have changed, could a reunion between Lohse and the Cardinals be in the works? Mozeliak didn't make it sound all that likely.
"Any time we discuss free agents -- whether it is early in the free-agent market or now -- it's not something we publicly go about doing," Mozeliak said. "In terms of how we look at our staff right now, we do have confidence in what we have. If something makes sense for us and as a group, if we feel like it's in our best interest to consider, we may. But I don't want to get into specifically talking about one player today."
The competition for the Cardinals' open rotation spot will begin next Tuesday, when the Cardinals hold their first spring workout.