VIERA, Fla. -- Nationals right-handers Jordan Zimmermann and Collin Balester are battling for the fifth spot in the rotation.

On Wednesday afternoon against the Mets, both pitchers were on the mound with Zimmermann outpitching Balester. Zimmermann pitched three shutout innings without giving up a hit, while Balester gave up four runs in three innings.

Zimmermann, 22, has now pitched five shutout innings this spring without allowing a baserunner and showing the Nationals why he was named the team's Minor League Pitcher of the Year in 2008. Pitching coach Randy St. Claire said Zimmermann is not your ordinary rookie. He doesn't try to throw harder to impress manager Manny Acta. Zimmermann's poise reminds St. Claire of left-hander John Lannan.

"He has a great arm, great feel for pitching -- those are the guys that are special," St. Claire said about Zimmermann. "He can execute everything. He can spot that fastball and he does it. You don't see Zimmermann [trying to throw the ball harder]. He is just going out there and pitching. All he is concerned about are his pitches and execution. He executes everything. He is special."

Zimmermann said he never felt any better than he did on Tuesday.

"My confidence is real good right now," Zimmermann said. "I just try to go up there and put up zeroes every time. I got a lot of ground balls and the defense made a lot of nice plays today. It was just one, two, three and I was out of there.

"Once you get ahead of the hitters, then you have them right where you want them. You can throw what you want to throw instead of throwing the fastball when you get behind."

Balester had only one bad inning -- the fifth. He gave up a solo home run to Fernando Tatis and a three-run shot to Ramon Castro.

'He got some [fastballs] over the plate," St. Claire said. "The wind is blowing out to right field. It doesn't take much to get out of there. He fell behind, 1-0, to Castro, who is a fastball hitter."

In the sixth, Balester was able to get out of the inning by throwing six pitches -- all for strikes.

"I was happy the way he threw the ball -- bouncing back the very next inning," Acta said. "That was a good comeback by the kid."