Phil Nevin homered, doubled, and drove in five runs and the San Diego Padres built a big lead for Jake Peavy in beating the Mets 9-4 last night.

San Diego got off to a good start, roughing up newly promoted Aaron Heilman in going ahead 5-0. Mike Cameron rallied the Mets with a three-run homer in the sixth inning, then Nevin broke it open with a three-run shot in the eighth.

Heilman (0-1) lasted only 3 2 /3 innings after being called up from Triple-A Norfolk earlier in the day to pitch in the majors for the first time this season. He took the place of Matt Ginter, who was designated for assignment in Norfolk.

Heilman gave up four runs, and it could’ve been worse as he allowed eight hits and three walks.

Nevin had an adventuresome evening. He hit a two-run double in the first, singled and scored on a wild pitch in the fifth, and later added his 17th home run.

Peavy (10-3) began the game with a 2.08 ERA, best among major league pitchers with at least 100 innings. Having missed six weeks because of strained right forearm, he may not pitch enough – 162 innings, in most cases – to qualify for the ERA title.

Peavy blanked the Mets on a lone scratch single for five innings. He remained unbeaten since July 7, winning five times in eight starts during that span.

Mark Loretta drew a one-out walk in the first, Brian Giles doubled and Nevin also doubled for a 2-0 lead.

Sean Burroughs and Freddy Guzman hit RBI singles in the fourth. A wild pitch by Dan Wheeler with the bases loaded and Peavy batting with a 1-2 count brought in another run.

The Mets’ only early threat against Peavy came in third after he hit Cliff Floyd around the right elbow with a pitch to load the bases.

Floyd made a perfect throw from left field to cut down Ramon Hernandez at the plate the next inning. Floyd left after that for X-rays on his arm, which were negative.

Gerald Williams took over for Floyd and doubled to lead off the sixth, and Hidalgo walked. Cameron followed with his 27th home run – extending his career high and also setting a Mets record for most homers by a center fielder, surpassing Tommie Agee’s 26 in 1969.

A single and two-base error by Nevin at first base let the Mets put the tying runs in scoring position later in the inning, but Scott Linebrink came in and retired rookie Jeff Keppinger on a foul pop and struck out Eric Valent to keep it at 5-3.

Nevin homered off rookie Bartolome Fortunato. Mets rookie David Wright homered in the eighth against Ricky Stone, and Loretta added a sacrifice fly