Cintron is a career .277 hitter in 598 games with the Arizona Diamondbacks and Chicago White Sox. He hit .243 with two home runs and 19 RBIs last season with the White Sox.
"He is a second baseman-shortstop," Orioles manager Dave Trembley said. "He's a switch hitter who has got experience playing in the big leagues. He gives us some depth. I've never seen him play before. We'll see what we've got."
Trembley said Freddie Bynum is his "shortstop until he shows he can't do it," while the 29-year-old Cintron will be primarily a utility player.
Cintron was in spring training with the Chicago Cubs, but was released. The Orioles signed him to a minor league contract and he hit .288 in 16 games with Norfolk.
"I'm so happy right now I'm here and to be back in the big leagues," Cintron said. "Hopefully, I can fit well and help the team win games. I'm glad they've given me the chance."
Second baseman Brian Roberts, who left Saturday's game with a bruised left foot, and catcher Ramon Hernandez, who was a late scratch Saturday with soreness in his left wrist, were not in the starting lineup Sunday against the Kansas City Royals.
Trembley said both could play, but with the day off Monday that both should be ready to go Tuesday against the Boston Red Sox.
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