The Baltimore Orioles placed outfielder Nolan Reimold on the 15-day disabled list on Friday with a herniated disk.
Reimold was off to a hot start to the season by batting .313 and had a 14-game hit streak in April.
The move is backdated to May 1, so he is eligible to be activated on May 16.
In his place, the club called up catcher Luis Exposito from Class AAA Norfolk to make his major league debut. Exposito was claimed off waivers from the Boston Red Sox on April 17. He is hitting .310 in 10 games with Norfolk.