HOUSTON -- In posting their second shutout victory of the season Sunday, Houston capped an interleague series win over the Cincinnati Reds and set the stage for a critical three-game set against the Los Angeles Angels, who will arrive 21/2 games behind the third-place Astros in the American League West.

The Astros improved to 14-7 in their last 21 games, 17-8 in their last 25 and 27-19 since May 1. And while the Rangers keep winning atop the division -- Texas extended its winning streak to six games by completing a sweep of the Cardinals in St. Louis on Sunday -- the Astros are measuring progress by series victories and focusing on that singularly.

"We're inching our way back towards relevance," Astros manager A.J. Hinch said. "We've got to tweak a few things here and there. We've got to continue to pitch well. Our offense seems to be warming up throughout the order. That's a good sign.

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"It's important for us to continue to play good. If we play well and play clean baseball we're going to be fine. I like our team. I think we have talent, I think we have a little bit of an attitude these days that we expect to win which is good. Our confidence isn't shy, our swagger isn't low."

With right-hander Doug Fister (7-3, 3.26 ERA) scheduled to start the series opener against the Angels (31-38), the Astros (34-36) should like their chances to keep streaking. Houston is 9-0 in the last nine games Fister has started, with Fister posting a 6-0 record and 2.35 ERA during that stretch. Fister did not factor into the decision in the Astros' 8-6, 13-inning victory in Anaheim on May 29 after surrendering just one earned run on five hits and four walks with six strikeouts over six innings.

The Angels, who completed a series victory over the Athletics on Sunday behind right-hander Jered Weaver and his three-hit shutout, will pay their first of three visits to Minute Maid Park.

Right-hander Jhoulys Chacin (3-4, 5.00 ERA) will get the start for the Angels, who have won four of five after a 1-7 stretch. The Astros won two of three when the teams met for the first time late last month.

Chacin is 1-1 with a 7.04 ERA in three June starts and 2-2 with a 4.75 ERA since the Angels acquired him from the Braves on May 11. Chacin is 1-1 with a 3.15 ERA in three career starts against the Astros. In his lone appearance at Minute Maid Park, he allowed two runs on five hits and one walk with nine strikeouts in seven innings while with the Rockies.

With left-hander Hector Santiago and righty Matt Shoemaker set to follow against the Astros, the Angels need Chacin to produce a positive start to not only set a tone but to maintain the momentum Weaver generated.

"The rotation sets the tone, and it's the heartbeat of your club," Angels manager Mike Scioscia told MLB.com. "Ours needs to do what we saw this week on a more consistent basis."