Kathy Willens/AP

Anthony Rendon, the Nationals top prospect who was called up Sunday to play third base while Ryan Zimmerman is on the disabled list, will return to Class AA Harrisburg when Zimmerman is healthy, Manager Davey Johnson said.

Johnson said there was “not really” a scenario in which Rendon would stay in the majors past Zimmerman’s return. Zimmerman was placed on the disabled list Sunday, backdated to Thursday, and could be eligible to return on May 3 in the series opener against the Pirates in Pittsburgh.

“I don’t care if [Rendon] hits .900 he’s not going to beat out Ryan Zimmerman,” he said. “And he’s our third baseman. And what he needs more than anything is playing time. He hasn’t really had a full season professionally. So he just needs to get some games under his belt.”

Rendon, 22, went 0 for 4 with two strikeouts and an error in his major league debut against the Mets in New York. The infielder, a natural third baseman with a sweet swing and quick wrists, played in only 43 games last season because of a fractured ankle. It was his first professional season since being picked sixth overall in the 2011 draft.

A hamstring injury to Zimmerman forced the Nationals to call up Rendon sooner than they expected. The Nationals brought Rendon up from the minors so he could play, not to sit on the bench and stall his development. If he starts every day until Zimmerman’s soonest return date, he will have played 12 games.

“He had a rough year last year with injuries,” Johnson said. “But he had a great spring for us and he’s been playing good down in Harrisburg. I’m sure he’s looking forward to tonight. He’s pretty low key. He didn’t look real nervous in the game the other day. But being in front of a home crowd is probably going go to be a little more exciting for him.”

Rendon, a laid-back Texan, admitted he was nervous before his major league debut. Having his parents, Bridget and Rene, in the stands in Washington on Monday is sure to help. They purchased plane tickets from Houston to New York but because of an issue with the airline weren’t able to make it to the game. Instead, Rendon said his parents’ detour took them through Philadelphia then Baltimore before finally arriving in Washington.

“Obviously you’re going to have extra nerves in your first big league game,” he said Sunday. “You don’t know what to expect. There’s 30,000 people in the stands instead of the 100 you’ve been playing in front of in the minor leagues. It’s good. You just try not to take the game out of context. The game is the same.”