Second baseman Skip Schumaker (strained right triceps) and outfielder Allen Craig (strained left groin) on Tuesday were placed on the 15-day disabled list before the St. Louis Cardinals' game against Washington.
Schumaker hasn't played since Friday; Craig last played Saturday.
Cardinals manager Tony La Russa said Schumaker's injury appears to be more serious than Craig's, and that Schumaker likely will require longer than two weeks before he's ready to return to the lineup.
"I think Skip's longer," said La Russa, who replaced Schumaker with Tyler Greene in the game Tuesday. "You should ask the trainers or the doctors, but I don't think it's 15 days. I think it will be longer than 15."
Taking Schumaker's and Craig's spots on the roster are first baseman/outfielder Mark Hamilton and infielder Nick Punto. Hamilton figures to be used as a pinch-hitter, while Punto can play third base, shortstop and second base.
Punto will wear No. 8. Hamilton will wear No. 38.
Schumaker is batting .241 with one homer and eight RBIs in 14 games. Craig enjoyed a strong road trip and is batting .313 with one homer and seven RBIs in 11 games.
Craig suffered the injury stealing second base Saturday.
"I just felt it grab me a little bit and I thought it would be best to come out of the game before I blow it out real bad," he said. "It was sore the next day and the day after that. I don't think it's anything serious. It's just kind of a precautionary deal. It takes a little bit of time to get it 100 percent.
"It's frustrating, but you try not to think about it too much. I'll come back in 13 days or whatever it is."
Hamilton, a left-handed hitter, was batting .297 (11-for-37) with two doubles, one homer and four RBIs in 11 games with Class AAA Memphis. He had a .469 on-base percentage, with 12 walks and seven strikeouts.
"It's wonderful to be back," Hamilton said. "It's a great clubhouse to be in. You never want injuries to happen, but when they do happen, you've got to be ready. I'm excited to be here."
Hamilton, 26, said he's "comfortable out there" in the outfield, although it's not his natural position.
"I played out there in college (at Tulane) and I've been working on it during BP and stuff like that," Hamilton said. "I feel like if I get the reps I need and I work on it, I can be good out there."
Hamilton won't receive consistent at-bats like he's been accustomed to at Memphis, which present him with a challenge
"It's always difficult to hit off the bench," he said. "At the same time, you just try to stay with your approach, stay ready to hit and be ready when you're called upon.
"I definitely feel like I'm ready to come up here and contribute. It's just going to be seeing how long I can be up here, how long they need me. At the same time, I'll try to do the best I can off the bench. I've been swinging the bat real well, especially the last week or so, down there. I feel pretty confident and comfortable."
Punto, 33, signed as a free agent in the offseason, was recovering from a sports hernia suffered early in spring training. He had been playing against Cardinals minor-leaguers in the team's extended spring training in Jupiter, Fla.
"It was a modified spring training for me --about 10 days of work" Punto said. "But it was a lot of at-bats (15) and as far as the injury's going, I feel great. I feel healthy and I'm thrilled to be here. The medical staff and training staff has been outstanding, putting me in a position where I'm at right now."
La Russa said the switch-hitting Punto probably will start the second game of the series against Washington on Wednesday. Daniel Descalso joins Greene and Punto as possibilities to start while Schumaker is sidelined.
"They're three good options, so we're in good shape," La Russa said.
For more on the Cardinals, see Wednesday's News-Democrat or visit www.bnd.com.