Cardinals pitcher Trevor Rosenthal spent the winter in St. Louis so that he could work out alongside Chris Carpenter, and as recently as last week the rookie watched the club’s veteran ace throw at Busch Stadium.
He didn’t sense anything was wrong.

Of course, it wasn’t really Carpenter’s style to ever let on when it was.

Rosenthal was one of several members of the club at its spring training facility who expressed surprise Tuesday when the Cardinals announced that Carpenter, a former Cy Young Award winner, is not expected to pitch in 2013 because of recurring issues with his right shoulder. General manager John Mozeliak described Carpenter’s return to the mound at all as “unlikely.”

“It’s a shock,” Rosenthal said as he left the club’s complex at Roger Dean Stadium. ”He’s a tough guy. He never complained about anything. … He looked good. Everyone knows what he means to this team.”

What it means for the team is that Rosenthal and three other young pitchers are in a competition for, suddenly, one more opening in the rotation. The Cardinals planned to enter spring training with four pitchers – Rosenthal, Joe Kelly, Shelby Miller and the incumbent, Lance Lynn – vying for one spot in the rotation. Carpenter’s absence means the four pitchers will audition for two spots in the five-man rotation.

This might seem familiar. A year ago, Carpenter experienced numbness and irritation as a result of nerve damage in his right shoulder. The same symptoms wouldn’t relent last week and led to Tuesday’s announcement. A year ago, Lynn emerged as Carpenter’s replacement and won 18 games and an All-Star Game invitation.

“We have seen this because we went through a lot of last year without Carp,” pitching coach Derek Lilliquist said. “There are a whole lot of tremendous accolades that I can (give) Carp and what he means. I also know that the guys can step up. We saw that. We just need to figure out which direction we’re going to go with it.”