Astros left-hander Framber Valdez entered Thursday trailing only Justin Verlander on the Houston staff in innings pitched, having worked at least six innings in four consecutive starts.

That Valdez delivered seven strong innings in the Astros' 5-1 victory over the visiting Texas Rangers in the opener of a four-game series was not a surprise. However, it certainly qualified as welcome for Astros manager Dusty Baker, who continues to judiciously allocate innings for his pitchers while in the midst of playing 33 games over 34 days.

The Rangers will attempt to even the series when the teams meet again Friday night.

Valdez completing seven frames enabled Baker to use just two relievers in the series opener: right-handers Hector Neris and Ryan Pressly, who each struck out three batters in one perfect inning. It also allowed Baker to steer clear of two high-leverage relievers who pitched in the series finale against the Boston Red Sox one night earlier.

"We were trying to stay away from (Rafael) Montero and trying to stay away from (Ryne) Stanek because they pitched (Wednesday). And Blake Taylor," Baker said. "So if Framber only goes six, then I would have had to use one of the guys I was trying to stay away from."

Right-hander Cristian Javier (2-1, 3.20 ERA) has the starting assignment for the Astros on Friday. He took the loss in his previous outing after allowing seven runs on eight hits and three walks with five strikeouts over 3 2/3 innings in a 13-6 setback to the Washington Nationals on Saturday.

Javier had allowed just two runs on 11 hits and six walks over his previous six appearances (two starts). His first start of the season came against Texas on April 27, when Javier allowed two runs on four hits and two walks with four strikeouts over five innings in a 4-3 road victory.

He is 4-0 with a 2.95 ERA over nine career appearances (five starts) against Texas.

Left-hander Martin Perez (2-2, 2.01) is the scheduled starter for the Rangers on Friday. He ranks fourth in the American League and sixth in the majors in ERA and has yet to allow a home run in seven starts and 40 1/3 innings.

Perez is 2-0 with a 0.84 ERA over his past five starts, logging at least six innings in each outing. He earned a win against the Red Sox on Sunday, when he gave up one run on five hits and two walks with seven strikeouts over six innings.

Perez is 8-5 with a 2.89 ERA over 15 career starts against the Astros, his lowest lifetime ERA against any AL opponent. The eight victories are tied for his most against any team.

Perez retired 18 consecutive batters to open his start against Houston on April 28 yet did not factor into the decision. He ended up yielding one run on two hits and no walks with four strikeouts over seven innings in a game the Rangers lost 3-2.

Like his counterpart with Houston, Rangers manager Chris Woodward had several relievers slated for a day off Thursday, a list that included Matt Moore. However, the left-hander wound up pitching and surrendered a three-run double to Martin Maldonado with two outs and two strikes in the eighth inning.

The outcome didn't favor the Rangers, but rookie right-hander Glenn Otto producing career highs of six innings and 96 pitches helped save a Texas bullpen in desperate need of relief.

"We needed that," Woodward said. "That's going to give us a chance for the next three games to settle down and give those guys a blow down there."