May (arm) will be placed on the injured list Sunday and undergo an MRI once the team arrives in Chicago on Monday, Bill Plunkett of The Orange County Register reports.
Manager Dave Roberts said the right-hander felt a "shooting sensation" down his arm before being removed during the second inning of Saturday's loss to the Brewers, and there appears to be potential for a serious injury. May will miss at least one start while on the injured list, but the specifics of the injury won't be known until Monday, when he actually undergoes the MRI.