Cardinals All-Star catcher Yadier Molina has a partially torn ligament in his left thumb, and St. Louis hopes he might return during the regular season.
"I think this is sort of the best news we could hope for," general manager John Mozeliak said Monday.
Molina will be re-evaluated late this week or early next week.
"It'll really depend on how the next 5-7 days go," Mozeliak said.
St. Louis also cleared right-hander Adam Wainwright for baseball activities after he made a rapid recovery from a torn left Achilles, an injury sustained April 25. The two-time 20-game winner could help in the bullpen during the postseason.
"I've been watching him throw bullpens and watching him strut around," manager Mike Matheny said. "He's been telling everybody this was going to happen, so I don't know why we're surprised."
The Molina injury is the latest setback for a team that still had the best record in the majors. Outfielder Matt Holliday, first baseman Matt Adams have also missed considerable time and setup man Jordan Walden lasted just a month before being sidelined for the season with a shoulder injury.
"I think every team goes through this from time to time," Mozeliak said. "This year, hopefully that's what defines us."
Molina missed about two months with a torn ligament in his right thumb last season. The Cardinals said Monday the latest injury, to his glove hand, is not so severe.
Molina was hurt while tagging the Cubs' Anthony Rizzo attempting to score the tying run on a fly ball on Sunday.
Tony Cruz will be the everyday catcher for now for St. Louis, which led the NL Central by four games with 13 to go.
Molina was batting .270 with four homers and 61 RBIs and is widely considered the best defensive catcher in the game. Cruz was hitting .173 with one homer and seven RBIs with just 104 at-bats.
"It's always tough to fill someone's shoes, but Cruz has had opportunities in the past and last year he ended up being on the postseason roster because of what he showed," Mozeliak said.
St. Louis selected the contract of catcher Travis Tartamella from Triple-A Memphis, where he batted just .203 but was considered a defensive asset. First baseman Xavier Scruggs was designated for assignment.
Randal Grichuk started in left field following his recovery from an elbow injury. Grichuk entered with just nine at-bats in September and had not started since Sept. 9, when he had to flip throws to a fellow outfielder in a game against the Cubs.
"If he had to make a throw, he could do it," Mozeliak said.
Mozeliak said Wainwright would pitch a simulated game soon if all goes well. The Cardinals would need to see him pitch before the regular season ends to consider him for the postseason roster.
Wainwright was a standout as the the stand-in closer for injured Jason Isringhausen on the 2006 World Series title team.
"If you'll recall the last time he pitched out of the bullpen, he looked very good," Mozeliak said.