Johnson: Harper will need rehab assignment

CLEVELAND -- While the Nationals are in Philadelphia next week, outfielder Bryce Harper could be involved in baseball activities, according to manager Davey Johnson.

Johnson also indicated Harper will need to begin a rehab assignment, most likely at Class A Potomac, before he plays in a big league game. Harper has been on the disabled list since June 1 because of left knee bursitis. He originally hurt the knee on May 13 after crashing into the right-field wall at Dodger Stadium.

"He will have to go to Potomac, running around out there and seeing if the knee stays calm," Johnson said.