"When he was healthy he was one of the best," Mozeliak said. "He was blessed with talent but he also worked extremely hard. When I think back over the last 10 to 15 years here in St. Louis he was one of those guys who just helped create the model of success. He left nothing to chance."
Carpenter's contract calls for a $12.5 million salary this year, of which $2 million is deferred without interest and is to be paid in $200,000 installments each July 1 from 2017-26.
As recently as the Cardinals' annual fan gathering in mid-January, Carpenter was saying he was healthy and eager to pitch in 2013. Mozeliak said Carpenter tried throwing from a mound perhaps three times before calling him, emotionally saying he didn't think he could pitch.
"He felt to some degree he was letting us down," Mozeliak said. "I assured him nothing was further from the truth."
Still, Matheny called the news "a kick in the gut" and the Cardinals have been through this before, too. Adam Wainwright had Tommy John surgery after hurting his elbow in 2011 and missed the entire season.
"There are a lot of young arms ready to contribute and now they're going to get that opportunity," Mozeliak said.
He declined to speculate on whether the team would consider re-signing Kyle Lohse, who was 16-3 with a 2.86 in 211 innings for St. Louis last season but remains unsigned as a free agent.
The Cardinals also have uncertainty about left-hander Jaime Garcia, who was 7-7 with a 3.92 ERA last season but was limited to just 20 starts due to shoulder fatigue. He was lost for the rest of the postseason after injuring his left shoulder in Game 2 against the Nationals.
Wainwright, Jake Westbrook and Lance Lynn are expected to be in the rotation. Younger pitchers Joe Kelly, Trevor Rosenthal and Shelby Miller will compete for a spot.
"As we head into spring now there's certainly a void there, but there's also an opportunity," Matheny said. "We have to have some other guys step up."