WASHINGTON -- Bryce Harper suffered a right hamstring strain Thursday, and the Nationals prospect was put on the seven-day disabled list on Friday.

Harper had to leave the game against Double-A Akron because of the injury.

It occurred in the eighth inning, according to reports. Harper, who plays for Harrisburg, hurt his hamstring while running from first to third on an Archie Gilbert double. Harper had to be helped off the field.

"I'm not going to worry a whole lot about Bryce Harper down there with a slight pulled hammy," Nationals manager Davey Johnson said. "It's the end of the season. He probably won't play the rest of the year. You are not taking a chance aggravating it where it becomes a more serious injury."

Elbow keeps Morse out of Nats' lineup

WASHINGTON -- Nationals first baseman Michael Morse was not in Friday night's lineup against the Phillies because of swelling in his left elbow. He is listed as day to day.

The elbow started to bother Morse after Washington's 3-1 victory over the Reds on Thursday night. Morse tried to convince manager Davey Johnson to let him play Friday, but the skipper declined. Morse was able to play catch before the game, but was not allowed to take batting practice.

"We are little bit worried that the [inflammation] will turn into tendinitis," Johnson said. "He tried to talk me into putting him into the lineup. I said, 'If we were fighting for a pennant, yeah.' But I have to be on the cautious side and be proactive, so I'm giving him the day off.

"The doctors think they can up his medication and stop the inflammation. It's right near the elbow joint. If you ever had a tennis elbow, you don't want that and try to hit a baseball."

Morse originally hurt the elbow on Aug. 11 after being hit by a pitch against the Cubs. He went to the hospital, and an examination showed that he had an elbow contusion. He missed only one game and returned to action.

In the top of the seventh inning with the score tied at 1, Morse was behind the count, 0-2, when Cubs right-hander Ryan Dempster hit him on the elbow. Morse was in serious pain as he walked to first base before Johnson and assistant athletic trainer Mike McGowan came to his aid.

"I got hit in the elbow. They're taking proper precautions," Morse said. "It feels like it's been feeling. I guess it's better to take a day now than take a day later."

In Morse's absence, Laynce Nix will play first.

Nats' Johnson could see Pudge return in 2012

WASHINGTON -- Nationals catcher Ivan Rodriguez, who is on the disabled list because of a right oblique strain, is still unable to hit, but doesn't have any problems throwing the baseball. Rodriguez was hoping to hit in the cage this weekend, but manager Davey Johnson indicated that it will be a while until that happens.

Johnson is hoping Rodriguez is activated when the roster expands sometime in September. Johnson also said he would like to have Rodriguez back for next season. However, Jesus Flores could determine if Rodriguez returns to Washington. Flores is trying to show that he can be productive as a backup catcher.

Entering Friday's action against the Phillies, Flores is hitting .244 with a homer and one RBI in 15 games.

"Anybody would be crazy not to have him back," Johnson said about Rodriguez. "He is a tremendous talent. He has been great here this year. He is fun to have around. He can hit, he can catch, he can throw and he adds to our depth at catching. He is a valuable asset. It just depends on the roster and what goes on over the winter and what our needs are.

"It's also a valuable time for Flores to try to regain the status that he had a couple of years ago. That will weigh more than Pudge coming back. Everybody knows what Pudge can do."