WASHINGTON -- This wasn't a night for experimenting, so Mets pitcher Mike Pelfrey didn't mess around with fancy pitches like sliders and changeups.

Pelfrey offered a steady diet of fastballs, and though he allowed nine hits, he kept the damage contained and helped the Mets to a crucial 8-4 victory over the Nationals on Wednesday night.

"This was probably the biggest start of his career tonight," catcher Paul Lo Duca said. "He threw the ball well."

Pelfrey took the mound because of an injury to Orlando Hernandez, and his start came at a critical time for the team. The rookie took the mound and ended the Mets' five-game losing streak, helping his team boost its lead over the Phillies in the National League East back up to 2 1/2 games. But he said that none of that was on his mind.

"I blocked it out," he said. "It never really bothered me. I think I did a pretty good job of blocking it out. I was there to win a game -- same thing I always do."

The tall right-hander has come a long way since losing seven of his first eight games in his debut season. Since rejoining the team at the beginning of September, Pelfrey is 3-0 and has earned the confidence of manager Willie Randolph.

Randolph said the team would continue to rely on Pelfrey.

"He's maturing, and he's still finding his way, but we need his stuff," the manager said. "He might give up a few hits here and there, but he also broke some bats. It was a good outing for him. It's nice to see him progress."

Pelfrey recorded four strikeouts, three of them against leadoff hitter Nook Logan. He gave up hits, but was able to make pitches at key times, stranding five runners while allowing just three to score.

The Nationals' offense proved especially potent in the series, scoring 21 runs in the first two games, and Pelfrey gained respect for them Wednesday.

"They hit the ball. I'm going to go back and watch the video, but some of them were good pitches," Pelfrey said. "The guys played good defense, and I was able to get through it."

He also got key support from the offense and bullpen, which put him in the position to succeed early. As Pelfrey finishes out his first Major League season, he can feel himself maturing as a pitcher.

"I see it in myself, that I'm getting better," Pelfrey said. "I said all along that I'm going to get more comfortable as I go, and I feel like I'm doing that."