(Sports Network) - Houston ace Roy Oswalt will try to put a recent poor performance behind him tonight, when he leads the Astros versus the Philadelphia Phillies in the opener of a four-game series at Minute Maid Park.

Oswalt was 4-0 in six starts before losing his last outing on Saturday against the Texas Rangers at Arlington. He ended his unbeaten by allowing six runs and 11 hits through six innings of a 6-2 loss. It was Oswalt's third start this season with at least 10 hits allowed and five runs earned, and dropped his record to 4-4 with a 5.43 ERA in 10 starts this season.

The right-hander defeated Philadelphia on April 16, countering Thursday's opposing hurler Kyle Kendrick with seven stellar innings of one-run, five-hit ball in seven frames. Oswalt is an impressive 6-1 with a 2.79 earned run average over nine career appearances (seven starts) against the Phillies.

Houston won the last two games of a three-game series with the Chicago Cubs and improved to 14-5 this month following last night's 5-3 victory. Carlos Lee belted a three-run homer, while Miguel Tejada and Geoff Blum each drove in a run for Houston. Starter Shawn Chacon posted his first win of the season after hurling seven strong innings of three-run ball. He finally ended his major league-record nine consecutive no-decisions by a starter to open a season.

Jose Valverde tossed a scoreless ninth to earn his 14th save. The Astros closer has compiled a 17 2/3 scoreless innings streak, trailing only Philadelphia starter Cole Hamels (19) for the longest active such streak in the majors. Valverde has also registered 12 straight save opportunities.

The Phillies enter this four-game set having won the last two installments of a three-game series against Washington at Nationals Park. After losing the opener by a 4-0 score and winning the second test, 1-0, Philadelphia broke out its renown bats in a 12-2 pummeling of the Nats on Wednesday. Ryan Howard continued to break out of his slump by belting a pair of homers and driving in four runs for the Phillies, who are tied with Atlanta at 1 1/2 games behind Florida for NL East supremacy.

Shane Victorino ended 3-for-5 with three runs scored, Pedro Feliz added a home run and Chase Utley, Jimmy Rollins and Chris Coste each collected a pair of hits, a run scored and an RBI in a winning effort.

Starting pitcher Jamie Moyer scattered seven hits and a walk over six scoreless innings and Clay Condrey tossed the last three frames, giving up two runs on five hits to pick up his first save of the season.

Kendrick hopes he can get the same kind of run support when he takes the ball for the Phillies tonight. Kendrick threw just 12 pitches in the first inning of his last outing on Sunday versus Toronto because of a rain delay.

Kendrick, who is 3-2 with a 4.76 earned run average in nine starts this season, obviously did not factor in the outcome of that 6-5 loss to the Blue Jays at Citizens Bank Park. He is 2-0 over his last six trips to the hill, with the Phillies going 5-1 during that stretch.

The second-year righty faced Houston for the first time on April 16 this season and was saddled with the loss. In the 2-1 setback at Citizens Bank Park, Kendrick was reached for a pair of runs and four hits in seven innings.

Philadelphia won two of three games versus Houston from April 15-17 at Citizens Bank Park. The Phillies are 9-6 over the previous 15 matchups with the Astros.