Astros 4, Pirates 1: Jason Castro belted a three-run homer in the seventh inning to snap a tie and Dallas Keuchel tossed seven solid frames as host Houston dealt Pittsburgh another blow to its faint postseason hopes.
Gaby Sanchez went deep in the second inning for his fourth homer with the reeling Pirates, who suffered their fifth straight loss and 30th in 41 outings. They fell 6 1/2 games back in the race for the second wild card after St. Louis recorded a 5-4 triumph over the Chicago Cubs earlier on Saturday.
Jed Lowrie extended his hitting streak to seven games by leading off the seventh inning with a single. After Matt Dominguez reached on shortstop Clint Barmes' error, Castro deposited an offspeed pitch from Kevin Correia (11-10) just over the wall in right field for his third homer - and first since June 25.
The blast made a winner out of Keuchel (3-7), who allowed one run on four hits and struck out five. Hector Ambriz bridged the gap to Wilton Lopez, who retired the side in the ninth for his seventh save.
Brett Wallace had an RBI single to drive in his third run of the series for the Astros, who improved to 10-10 in September.
GAME NOTEBOOK: Correia suffered the hard-luck loss after matching a career high with nine strikeouts. The right-hander has reached nine strikeouts on three occasions. ... Pittsburgh has been outscored 29-10 during its losing skid. ... Pirates rookie Starling Marte, who went 1-for-4, has five hits in his last three games.