Nationals right-hander Stephen Strasburg allowed just one hit over six shutout innings in a rehab start for Double-A Harrisburg on Thursday night. The appearance is expected to be his final rehab start before he returns to the major leagues. Strasburg struck out four and threw 70 pitches, 53 for strikes. It was his sixth rehab appearance since undergoing Tommy John surgery to repair a torn ulnar collateral ligament in his pitching elbow last September. "I think the work isn't done. I need to keep on grinding, finish the season strong here and go into the offseason healthy," Strasburg said. "See what kind of pitcher I am in 2012."