Jeff Karstens pitched 6 2/3 scoreless innings to outduel Bud Norris and the Pittsburgh Pirates edged the host Houston Astros 1-0 on Tuesday in the opener of a three-game series.

Houston's Hunter Pence went 0-for-4 to halt his hitting streak at 23 games.

Garrett Jones singled home the lone run and Andrew McCutchen extended his hitting streak to 13 games as the Pirates improved to 18-15 away from home and surpassed their road win total from a year ago.

Karstens (4-4) allowed three hits to earn his first win since May 20 and help Pittsburgh snap a nine-game losing streak at Minute Maid Park.

Four relievers bridged the gap to closer Joel Hanrahan, who secured his 18th save in as many chances.

Norris (4-5) went seven innings and limited Pittsburgh to one run on six hits. He struck out nine and walked two.

The Pirates pushed across the only run in the second when Neil Walker led off with a single, moved to second on a wild pitch and scored on a single by Jones.