Bud Norris tossed six scoreless innings and Jason Castro homered as the Houston Astros claimed a 3-0 victory over the Chicago Cubs in the middle portion of a three-game series.
Norris (7-13) allowed only four hits and a pair of walks while striking out four, and Tyler Greene added an RBI single for the Astros, who surged to their fifth win in six games.
"The team won three in a row. That's the way we're looking at it. We're trying to end this thing strong and play it all the way through," Norris said about his team's late push.
Chris Volstad (3-12) gave up five hits and one earned run with six strikeouts for the Cubs, who were blanked by the same score for the second straight game and lost for the ninth time in their last 10.
"Not a lot of quality at-bats again. We left some guys out there striking out with guys in scoring position again," Cubs manager Dale Sveum said. "It's kind of typifying the whole season these last two nights swinging the bats."
Houston picked up all the runs needed to back Norris in the second, all coming with two outs. Castro's shot to right was followed by a Starlin Castro error allowing Justin Maxwell to reach second. Greene drove him in with a single for a 2-0 score.
The Astros tacked on another run in the eighth, as pinch-hitter Brian Bogusevic drew a walk, moved to second on an error, advanced to third on a Jed Lowrie groundout and scored on a wild pitch.
After Norris' exit, four Houston relievers combined to hold the Cubs hitless over the final three innings. Wilton Lopez walked Luis Valbuena with two outs in the ninth, but induced a game-ending pop out from Welington Castillo to earn his 10th save.
Norris finished the 2012 season with 13 1/3 scoreless innings over his last two starts ... Chicago was shut out for the third time in its last seven games ... Houston has recorded three consecutive whitewashes, having earned a 7-0 victory at Milwaukee on Sunday.