To take their roster spots, the club activated infielder Nick Punto from the 15-day disabled list and recalled first baseman Mark Hamilton from Triple-A Memphis. Craig suffered a strained left groin and expects to be out for only the minimum 15 days.
"It's a little disappointing," Craig said. "Obviously, I want to be out there and playing, but it's a long season. I'll be out for 13 days or whatever it is, and I'll get it right and come back swinging again."
Manager Tony La Russa said that Schumaker, who has a strained right triceps, will likely miss more time than that.
Schumaker said he didn't have a frame of reference for the injury.
"Going into it, I didn't know what to think because it could have been a lot worse, a whole lot worse," Schumaker said. "So hopefully I can have a speedy recovery. But I've never had an elbow injury or anything I can base it on."
Punto, Tyler Greene and Daniel Descalso will share time at second base in Schumaker's absence. Greene got the first start, but all three are expected to see time. Descalso can also play third base, while Greene and Punto are adept at both shortstop and third. Punto, in particular, is considered a top-flight defender at all three positions, making him a valuable addition to the Cardinals.
Punto had been out since early in Spring Training due to a sports hernia. He had spent approximately a week playing in extended spring camp to get ready for his return. His activation was accelerated somewhat due to Schumaker's injury, but Punto said Tuesday that he's in shape for games.
"The game plan was to get a couple more games, but I was ready to play," he said. "That's what I expressed to [general manager John Mozeliak], is that I'm ready to play."
Hamilton will get some of Craig's at-bats as a pinch-hitter, but there will probably be less time available to him in the outfield. He is a first baseman by trade, but La Russa said he's willing to play Hamilton in the outfield if needed.
Relievers Brian Tallet and Bryan Augenstein were both placed on the 15-day disabled list on April 13 due to injuries they suffered in Arizona.
Matthew Leach is a reporter 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.