Washington Nationals outfielder Bryce Harper has been cleared to begin testing his injured knee a week after receiving a cortisone shot and a platelet-rich plasma injection into the joint, according to local media reports. Harper, placed on the disabled list June 1 for bursitis in the left knee, will be evaluated closely as he continues his rehabilitation, which can resume with walking, jogging and other weight-bearing activities, team trainer Lee Kuntz said. "You have to see how he reacts to the one thing before you can add the second," Kuntz said Monday. "Otherwise you're trying to cut out steps and that doesn't work. We'll do baseball activity once he's able to do other functional ground-based activities like running. Running is the key, for me." Harper was given the injections after visiting noted orthopedist Dr. James Andrews last Monday in Florida. Harper hasn't played since May 26 and had been bothered by the knee since he crashed into the outfield wall chasing a fly ball two weeks earlier. The 20-year-old star is batting .287 with 12 homers and 23 RBIs.