JUPITER, FLA. (AP) - Washington manager Davey Johnson says Mike Morse has had platelet therapy to help heal a back muscle tear and his availability for opening day is uncertain.
Morse has appeared in only three games this spring as the designated hitter after hurting his back early in spring training.
He previously received a cortisone shot to treat the injury. He returned for two more games following the injection, but hasn't played since March 13.
On Thursday, the Nationals begin a series of three straight road games, starting with the Cardinals. Morse did not accompany the team to Jupiter, Fla.
Morse is coming off a breakout season in which he hit 31 home runs and drove in 95 while posting a .303 average.