(Sports Network) - Houston right-hander Roy Oswalt shoots for his 12th career win against Pittsburgh tonight, when the Astros head to PNC Park for the second of three games with the Pirates.

Oswalt is 11-5 in 22 career games against the Pirates, including 21 starts, with a 2.49 earned run average in 148 innings of work. He has walked just 24 batters in that stretch, while striking out 126.

The 30-year-old Mississippi native is winless in three starts since the end of a four-decision win streak this year. In a 3-2 loss at St. Louis on May 29 he allowed five hits and three runs in seven innings of work.

He dropped a 6-2 decision at Texas on May 17 after being tagged for 11 hits and six runs in six innings. Oswalt's last win came May 12 at San Francisco, when he tossed eight innings of five-hit, three-run ball.

For Pittsburgh, lefty Zach Duke will attempt to end a three-start winless skid on Wednesday night.

Duke won consecutive starts on May 6 and May 12 against San Francisco and Atlanta to even his record at 2-2, but has since gone 0-2 with a no-decision in three outings.

He allowed five hits and two earned runs in six innings against St. Louis on May 30, dropping a 5-4 verdict. He previously lost a 12-3 decision on May 23 against the Chicago Cubs, allowing 10 hits and four runs in four innings.

Duke is 0-3 with a 4.08 ERA in seven lifetime games against Houston.

On Tuesday, Wandy Rodriguez and three relievers combined on a five-hit shutout as the Astros topped the Pirates, 2-0.

Rodriguez improved to 2-1 after striking out three batters and walking one in six innings. Chris Sampson, Doug Brocail and Jose Valverde followed with three hitless innings of relief, with Valverde notching one strikeout en route to his 16th save.

Lance Berkman doubled and drove in a run for Houston, which also got a double and an RBI from Miguel Tejada.

Jack Wilson had two of Pittsburgh's five hits. Lefty Phil Dumatrait (2-3) was a hard-luck loser after allowing seven hits and two runs in six innings.

Pittsburgh won 10 of its 15 matchups with the Astros last season.