Jeff Karstens pitched seven strong innings for the win, allowing a solo homer by Clint Barmes but little else. Karstens has allowed 17 home runs this season, but the Barmes homer was typical in that it was a solo job - Karstens challenges hitters when there's no one on.
Brandon Wood had a two-run homer and an RBI single for the Pirates, who also scored twice in the sixth, with an RBI single by Michael McKenry and a sacrifice by Karstens.
Wandy Rodriguez took the loss for the Astros, who, in a curious coincidence, also used Fernando Rodriguez and Aneury Rodriguez in relief.
Matt Diaz, Neil Walker and Lyle Overbay all had multi-hit games for the Pirates.
The Pirates will look to complete a sweep of the Astros at 7:05 PM Wednesday.
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