The Astros scored three runs in the first on a two-run homer by Carlos Lee and a solo shot by Matt Downs off Bucs starter Brian Burres. McCutchen homered in the bottom of the inning to make it 3-1.
Clint Barmes hit a solo homer in the fourth to make it 4-1, and the Pirates replaced Burres with the recently-promoted Jared Hughes, who recorded 1.1 scoreless innings in his big-league debut.
In the bottom of the fifth, McCutchen hit a three-run bomb to score Brandon Wood and Alex Presley and tie the score at four. Strong relief pitching by Daniel McCutchen and Chris Leroux carried the Pirates into the late innings, and Jason Jaramillo hit an RBI single to put the Pirates up 5-4. Joel Hanrahan picked up the save.
The Pirates are now 66-77 with 19 games remaining.
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