Manager Don Mattingly said Wednesday that Cooper is "a little nicked up" with a groin injury, Jordan McPherson of the Miami Herald reports.
Cooper didn't appear in Wednesday's win over Baltimore, and Mattingly revealed after the game that the 30-year-old was held out as a precautionary measure. Mattingly didn't sound too concerned about Cooper's injury, but it's not yet clear whether he'll be available for Thursday's series opener against the Giants.