Carpenter will miss his scheduled start on Monday, and any work beyond that is yet to be determined. If he were to return five days later, he could still make three starts prior to Opening Day. Pitching every fifth day, he could actually make four Spring Training starts, but that would require pushing back his scheduled Opening Day start on April 4 against the Miami Marlins.
Those matters are a little farther away than the club wishes to address right now, though. The Cardinals are looking for an explanation of the issue before they put any timetable on a return for the former National League Cy Young Award winner.
"Any time any of our guys feels something that isn't quite right, we're going to try to get him the best help we can," manager Mike Matheny said. "Check it all out, see what it is. It's too premature right now to say any more than what we know, which is [that] his neck's been tight. We'll just kind of adjust accordingly."
The worry is that Carpenter's condition is related to the nerve issues that plagued him in 2004 and 2008. He missed the entire 2004 postseason because of a nerve injury in his right biceps, and his attempt to come back from 2007 elbow surgery was short-circuited late in 2008 due to a similar issue in the back of his shoulder.
It has not been determined if there is any connection, general manager John Mozeliak said, but that is one of the possibilities being examined. At this point there's simply a great deal of uncertainty regarding the issue.
"It's still day to day," Mozeliak said on Friday prior to the Cardinals' 3-2 win over the Twins. "Nothing has really changed since yesterday. He was re-evaluated today. Based on what we see, maybe [we can] compare it to past history. So that's going to be done by some specialists in St. Louis, and then we'll have a better idea over the weekend.
"I don't want to get into the specifics of what we did this morning, but it is nerve-related."
Mozeliak emphasized that as of midday Friday, the club was merely examining whether there is a connection between the neck discomfort and the previous nerve issues.
"That's what they're checking to see," he said. "They're trying to get to the root of why. ... I don't want to characterize where we are mentally on this until we get more information. I think by the end of the weekend we should have a better idea, more clarity on the level of concern that we have."
Matthew Leach is a writer for MLB.com. Read his blog, Obviously, You're Not a Golfer and follow him on Twitter at @MatthewHLeach. This story was not subject to the approval of Major League Baseball or its clubs.