WASHINGTON -- Nationals outfielder Bryce Harper admitted Wednesday he is frustrated with having to watch from the bench.Harper was unable to be part of Players Weekend after going on the disabled list Aug. 13, one day after he hyperextended his left knee in a home game against the San Francisco Giants. A 2015 National League MVP, Harper told reporters he is "a long ways from running" prior to Wednesday's game against the Miami Marlins."If I wasn't an athlete and was just an average person, I probably wouldn't even be on it and doing anything," Harper said. "I'm thankful enough to be able to have a strong unit in there in the training staff to come in there every day and work hard and be able to do the things I need to do around my body that take a little stress off the knee area and calf area. (Also) certain things that can speed up recovery and speed up those places around it that I can be stronger again."When I come back, I don't have to rely on one muscle or one thing in my body to keep me going, I can rely on everything. That's what we're doing right now."There is no timetable for the return of Harper."I can sense a little frustration in his voice when I ask him how he's doing," manager Dusty Baker told reporters Wednesday. "Usually he's not a smart aleck, but lately he's been a little short in temperament. And I can tell that's because he wants to play. So I just leave it alone."Harper is hitting .326 in 106 games with 29 homers, 87 RBIs and a .614 slugging average.The Nationals (80-51) are on their way to second straight NL East title and fourth in team history, with the first coming in 2012.