Schumaker has a right triceps strain and Craig has a left groin strain. The moves were announced Tuesday before the start of a three-game series against the Washington Nationals.
Manager Tony La Russa thinks Schumaker, who's batting .241 with one homer and eight RBIs, will need more than 15 days to recover. Craig, who said he was injured while stealing second at Los Angeles on Saturday, is batting .313 with one homer and seven RBIs.
Schumaker said he was hurt on a swing and miss Friday night at Los Angeles. He's cautiously optimistic it won't be a long stay on the DL.
"I can't tell you it's going to be tomorrow, I can't tell you it's going to be six weeks, I can't tell you," Schumaker said. "I'm going to do everything I can to speed this up.
"It's just a weird thing, I can't really explain it."
Infielder Nick Punto was activated from the 15-day disabled list and first baseman Mark Hamilton was recalled from Triple-A Memphis. Punto missed most of spring training after surgery in February for a sports hernia and La Russa said he'd have been activated at some point this homestand, in any case.
"We've got three good options, so we're in good shape," La Russa said.
The 26-year-old Hamilton was a supplemental draft pick in 2006 out of Tulane and played nine games for the Cardinals last September. He was hitting .297 with one home run and four RBIs in 11 games at Memphis.