Pirates 5, Astros 3: Starling Marte homered on the first pitch of his major-league career to spark an early flurry and A.J. Burnett took a shutout into the eighth inning as visiting Pittsburgh won for the seventh time in nine games.
Marte led off the game by blasting a first-pitch cutter from Dallas Keuchel out to left. He is the third Pirate to homer in his first major-league at-bat, joining Walter Mueller in 1922 and Don Leppert in 1961.
Garrett Jones and Clint Barmes also went deep for the Pirates, who have hit 35 home runs in their past 16 road games to move to within two games of National League Central-leading Cincinnati.
Chris Johnson and Carlos Corporan hit solo homers for the Astros, who have lost 10 straight and 23 of 25 - the worst 25-game stretch in franchise history. Houston has been outscored 72-30 during its losing streak.
Burnett (12-3) continued his resurgent season, allowing two runs on four hits over 7 1/3 innings to win for the 11th time in 12 decisions. Johnson broke up the shutout with a solo homer into the Crawford Boxes leading off the eighth - his first homer since June 24. Corporan followed with his second homer later in the inning.
Joel Hanrahan allowed an RBI single to Johnson in the ninth before locking down his 30th save, tying Baltimore's Jim Johnson for the major-league lead.
Keuchel (1-3) settled in after giving up the three early homers, allowing five runs on five hits over six innings.
GAME NOTEBOOK: The Pirates have won seven straight against the Astros, outscoring them 40-20 during the streak. … Marte is the 28th player in major-league history to homer on his first pitch, and he is the first player to lead off his first major-league game with a homer since Kazuo Matsui did it for the Mets in 2004. … LHP Wandy Rodriguez, acquired from Houston on Tuesday, will make his Pirates debut against his former team Saturday. Fellow LHP Erik Bedard will have his next start bumped to Monday, and RHP Kevin Correia will move to the bullpen.