NEW YORK -- There was never a moment on Thursday when Chase Headley felt as though the Mets were discounting or overlooking him, even as Adrian Gonzalez spent the better part of the game being pitched around, both intentionally and unintentionally.

Short on service time, Headley, 24, certainly understood why the Mets wanted little to do with Gonzalez and everything to do with him, especially in critical situations when there were runners on base.

"When you're hitting behind Adrian, you know they're not going to give him much to hit. Adrian is such a great hitter. They're going to make the younger, less established players beat them," Headley said.

And that's exactly what happened, as Headley tied his career high with four hits and had three RBIs as the Padres topped the Mets, 6-5, at Citi Field before a crowd of 35,985, and took the second of three games in the Mets' new ballpark.

Headley, who only recently slid into the No. 5 spot in the order behind Gonzalez, contributed a two-run single in a five-run third inning for the Padres (7-3) and later added a double to score another run while Gonzalez, who walked twice and now has eight free passes in 10 games, spent the night running the bases.

The Padres, who have had seven of their 10 games decided by three runs or fewer, got to Mets starter John Maine (0-1) for five runs on four hits in the third inning. Headley's big single, which followed an intentional walk to Gonzalez, put the Padres on top, 4-3.

Two innings later, the Mets essentially pitched around Gonzalez to get to Headley again, and again he burned them for an RBI hit, this one a double.

"Chase has the potential to hit in the middle of the order. You have to remember, he has less than a year in the big leagues," manager Bud Black said. "We see that Chase can do some things offensively."

The fifth spot in the lineup, previously occupied by Kevin Kouzmanoff, is considered to be important because someone hitting in that spot has to produce offensively or, at least, represent a threat to do so, otherwise Gonzalez won't likely get much to hit.

"That five-spot is going to be very important for us to win games consistently. We have to get production out of that spot," Headley said. "You have got to want to be in that situation."

Headley's hot bat wasn't the only storyline on Thursday, as Jake Peavy worked past a slow start in which he burned through 44 pitches in the first inning, allowing a three-run homer to Carlos Delgado, a 440-foot blast, in the frame.

Peavy (2-1) got through five innings, allowing three runs on six hits with four walks and five strikeouts. The Mets (4-5) battled him the entire way, working into long at-bats by fouling off pitches they didn't like and working their way into deep counts.

"You have got to give credit to the Mets," Black said. "Every at-bat they were fighting the ball off and fouling the balls off. He was around the plate. Jake hung in there. He was awesome. He deserved the win, to me."

This was nothing Mets' manager Jerry Manuel hadn't seen before from Peavy, who will make his next start on Tuesday in San Francisco.

"That's why he is who he is. Despite his struggles and our battle with him, he never really gave in," Manuel said. "We had some chances to really get a knockout blow, but he kept hanging in there, making plays."

Peavy got his greatest satisfaction not from winning his second game of the season or the pitches he made -- the ones the Mets didn't foul off -- that became outs. Instead he talked about how satisfied he was with how the Padres overcame a 3-0 deficit and what they did to win for the sixth time in their last seven games.

"This is the most gratifying win I've ever been a part of," Peavy said. "It was a total team effort. I've got no problem with the way I pitched tonight. Right now I'm elated to walk away with a series win and a Padres victory."

Peavy turned the ball over to reliever Cla Meredith, who got three quick outs in the sixth inning. Edwin Moreno followed by allowing one hit in the seventh. But in the eighth, New York got a two-run homer by Ramon Castro off former Met Duaner Sanchez.

Finally, in the ninth inning, Heath Bell got Daniel Murphy and David Wright for the first two outs to set up an at-bat with Delgado, an 11-pitch tussle that included five foul balls and ended with Bell getting Delgado to look at a called third strike to end the game.

Bell has now saved five of the Padres' seven victories and hasn't allowed a run to date.

"There were some great at-bats tonight," Black said, not only referring to the Delgado at-bat in the ninth inning but several earlier in the game.