SAN DIEGO — Scott Hairston is making the most of his home runs for the San Diego Padres.

Hairston hit a three-run homer with two outs in the ninth inning Wednesday night, lifting the Padres over the Pittsburgh Pirates 5-3. The win increased San Diego's lead in the NL wild-card race to 2Z\x games over Philadelphia, which lost 2-1 in 10 innings at St. Louis.

Hairston, acquired in a trade with Arizona on July 27, also hit a game-winning, solo homer to give San Diego a 4-3 win in 10 innings on Aug. 3 against San Francisco. He entered that game as a defensive replacement and hit a three-run homer in the eighth to tie the game.

"He's made a couple of big swings since he's been here," Padres manager Bud Black said.

Hairston's homer gave San Diego its sixth straight win and allowed the Padres to stay one game off the NL West lead behind Arizona.

Hairston hit an 0-1 slider from Matt Capps (4-7) over the left-field wall. He had been just 5-for-30 (.167) with two outs and runners in scoring position this season.

The timely hit rescued the Padres, who had been held in check after scoring a pair of first-inning runs. San Diego had just three singles from the second through the eighth innings.

Gonzalez's double off the left-field wall nearly cleared the fence with one out. Kevin Kouzmanoff followed with a two-out walk before Hairston with his eighth home run, and was met by a wild celebration at home plate.

Cla Meredith (5-6) pitched a perfect ninth inning for the win.

"We did everything we could do," Pittsburgh manager Jim Tracy said. "Unfortunately, (Capps) was just an out away from a fabulous save."

Pittsburgh lost its fifth straight game.

All-Star Chris Young started for the Padres and was in danger of losing his fifth straight decision. He gave up three runs and five hits over six innings.

Ian Snell limited San Diego to one earned run and four hits in seven innings and said he left with a sore arm.