SAN DIEGO -- When Phil Nevin limped off with a knee injury on Sunday, Padres manager Bruce Bochy said the slack left by the team's cleanup hitter, and hottest hitter, couldn't be picked up by one player. Each member of the lineup would have to do his part.

Bochy's charges evidently listened.

Seven Padres contributed at least one hit Tuesday night, and Brian Giles and Mark Loretta slugged home runs as the Padres remained on a roll heading into the All-Star break with a 5-3 victory over the Houston Astros before 31,540 fans at Petco Park.

The Padres' fifth consecutive victory, and eighth in a row at home, kept them a half-game ahead of San Francisco in the National League West.

The Padres scored two runs in the first inning off Astros starter Pete Munro and never looked back, tacking on single runs in the third, fourth and fifth in support of right-hander Ismael Valdez. Loretta, the Padres' newly minted All-Star, gave them a two-run cushion with a solo homer in the fifth, and new cleanup man Ryan Klesko had two hits, including a key double in the first.

Valdez (7-5) wasn't especially sharp, as he pitched fewer than six innings for the third consecutive start. He faced the minimum through the first three innings but was hurt in the fourth by a defensive misplay by center fielder Jay Payton.

Payton allowed a low liner by Jeff Bagwell to skip off his glove and roll all the way to the wall. Payton's two-base error allowed two runs to score and Bagwell to end up at third base, where he was stranded.

Houston closed within 4-3 on Brad Ausmus' solo homer to left over the glove of a leaping Terrence Long before Loretta struck back with his own shot off a 3-1 pitch from reliever Mike Gallo for his seventh home run.

Giles also supplied some needed pop when he turned on an inside pitch from Munro and curled it around the right-field foul pole. Giles' 13th homer traveled 342 feet.

Tuesday's game was also noteworthy because of a return to form of setup man Akinori Otsuka. Bochy rested the right-hander the past two days after a confidence-testing stretch in which he allowed six runs and 13 hits in 5 2/3 innings. But Otsuka breezed through the eighth inning Tuesday, striking out one in a perfect frame, to follow fine relief work by right-hander Scott Linebrink.

Closer Trevor Hoffman wiped out a one-out walk in the ninth by inducing a double-play groundout by Morgan Ensberg. Hoffman recorded his 22nd save and third in the past four games.

The Padres quickly jumped on Munro (1-2), who lasted only four innings. Loretta hit a one-out single up the middle in the first and advanced to third on Klesko slicing double down the third-base line. Long then smacked a line drive into right-center field for a double that scored both runners.

After the Astros closed within 3-2 in the fourth, the Padres gave themselves some breathing room with three consecutive singles with one out, the last one a blooper by Khalil Greene to score Payton.

Contact staff writer Brian Hiro at b_hiro@hotmail.com.