PITTSBURGH -- Kevin Correia and Alex Presley used rare starts to make big contributions for the Pittsburgh Pirates.
"At this time of year, it's all about winning," Presley said. "You need everybody doing everything they can do to help the team win."
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Correia stepped into the Pirates' rotation for right-hander Jeff Karstens, who injured his right hip Friday in a start at Milwaukee, and allowed only one run and four hits. Correia also walked one and struck out one.
Correia (10-8) pitched four scoreless innings of relief against the Brewers in the game in which Karstens was injured. Correia began the season in the starting rotation but was bumped to the bullpen when the Pirates acquired left-hander Wandy Rodriguez from the Astros in a trade on July 24.
Houston fell to 53 games under .500 at 42-95.
Presley was playing in place of left fielder Jose Tabata, who bruised his left foot on Tuesday night when he fouled a pitch off it and still felt pain after taking batting practice before Wednesday's game.
Pirates rookie Brock Holt had two RBI one night after getting four hits in his fourth major league game and Gaby Sanchez had three hits for Pittsburgh, which pulled within 1½ games of St. Louis in the race for the second National League wild-card spot.
Correia reached double-digit victories for the fourth consecutive season.
"It's just a number but you do want to win as many games as possible because that's your job as a pitcher," Correia said. "The biggest thing you want to do, though, is give your team a chance to win."
Correia did that Wednesday when the Pirates needed him to come through after the Cardinals lost 6-2 to the Mets earlier in the day.
"He gave us a very professional effort," Pirates manager Clint Hurdle said. "He moved the ball in and out and kept them off balance. It was a good job."
Presley began the season as the Pirates' leadoff hitter but was twice sent down to Triple-A Indianapolis. He returned to the major leagues Friday with no guarantee of playing time.
"I had an inkling I might start because I saw Tabata hobbling around the clubhouse," Presley said. "Finding out late really didn't make a difference because I've started before. I'm just happy I was able to make a contribution."
Hurdle thought the good performance would be a confidence booster for Presley.
"He has to feel good about that," Hurdle said. "Alex can play and Alex can hit. The problem has been finding a consistent rhythm at this level."
Brandon Laird, yet another injury replacement, provided Houston's highlight with his first major league home run, a two-run, two-out shot in the ninth inning off Jason Grilli. Laird took over at third base in the sixth inning when Scott Moore strained his right groin while fielding a bunt by Holt.
Laird struck out swinging in his first at-bat in the seventh inning against Jared Hughes but was more prepared in the ninth.
"Everybody always tells me, be ready and that's what I was," Laird said. "I went in there and the first at-bat chased a couple bad pitches. I just wanted to go up there right there and see it before I swung and that's what I did and got a good swing on it."
Houston left-hander Fernando Abad (0-3) had another rough start in his conversion to the rotation from the bullpen. He was rocked for six runs -- five earned -- in four innings. Abad has lost all three starts and has an 8.03 ERA in those games.
Abad's poor performance cost Houston the opportunity to win the three-game series.
"I thought Abad could give us a chance but unfortunately we got down again early," Astros interim manager Tony DeFrancesco said. "It's getting frustrating for us."
Pittsburgh scored two runs off Abad in the first and another in the second to take a 3-0 lead. Garrett Jones and Sanchez hit consecutive RBI singles in the first and Holt singled in a run in the second.
After Houston got its lone run in the top of the fourth when Jimmy Paredes doubled and scored on Brian Bogusevic's single, Pittsburgh answered with two runs in the bottom half to increase its lead to 5-1. Presley tripled in a run and scored on a sacrifice fly by Holt.
A squeeze by Clint Barmes brought home a sixth-inning run for the Pirates.
Houston RF Fernando Martinez (skin irritation) was a late scratch and replaced by OF J.D. Martinez. ... Pittsburgh 2B Neil Walker (lower back stiffness) missed his ninth straight game, is unlikely to return Friday night for the opener of a three-game series against the Chicago Cubs as originally hoped. RF Travis Snider (strained right hamstring) sat out after being injured running the bases Tuesday but hopes to play on Friday. ... Houston expects SS Jed Lowrie (sprained right ankle) to begin an injury rehabilitation assignment this weekend after being on the disabled list since July 15 with a sprained right ankle. ... Both teams are off Thursday. On Friday night, Pittsburgh RHP A.J. Burnett (15-5, 3.63) will face Cubs LHP Travis Wood (4-11, 4.64) while Houston RHP Lucas Harrell (10-9, 3.81) will oppose Reds RHP Hector Bailey (10-9, 4.09) in the first game of a three-game series at Cincinnati.