PITTSBURGH -- Wednesday night's start is a big one for Pirates young lefty Zach Duke.

The 24-year-old is making his fifth start of the season. He began the season well, posting two quality starts, but has run into a rough patch with back-to-back subpar outings. Duke lasted two innings in a 8-5 loss to the San Francisco Giants on April 13 and got shelled for seven runs in four innings in a 7-3 loss at Milwaukee on April 18.

Duke has struggled with his command -- particularly with his fastball. He has not recorded a strikeout in three of his four starts this season.

"There's some factors," Duke observed. "It's to the point where I feel like I'm back in control and there should be some different results soon."

Duke said he examined a variety of factors to try to get back on track.

"There's a number of things," Duke said. "I think mostly it's just been kind of a focus thing. The focus has been in the wrong spot, and it hasn't been just on hitting the mitt -- it's been all over the place. I think that's really the main thing.

"You just kind of lose sight of what you're really out there to do. It's something that shouldn't happen, but it did and I've got to get back to where I was."

Pirates manager Jim Tracy feels it is imperative that they get Duke back in the groove.

"I think some of it has to do with his location with his fastball," Tracy explained. "I think he's leaving the ball on the plate a little bit more than you'd like to see, and when things like that happen, the ball is going to get hit. We need him -- because just like we've seen from Ian Snell and Tom Gorzelanny -- we want to get Zach Duke going, because over the course of a five-day period, you go through your rotation. If during the course of that five-day cycle, you get three or four guys that go out and give you a chance to win three or four times, and you start adding that up over the course of six months -- that gets to be pretty interesting.

"That's why we need Zach Duke, because Gorzelanny and Snell are throwing great and Zach Duke is very capable of throwing great."

Duke wants the ball and he is anxious to get back on the mound.

"Very, very anxious," he said.

Sanchez scratched: Defending National League batting champion Freddy Sanchez was a late scratch from the Pirates' starting lineup on Wednesday. Sanchez was removed because of right eye irritation and was replaced at second base by Jose Castillo.

Bucs-Giants: The Pirates and Giants will make up their postponed April 15 doubleheader on Monday, August 13 in Pittsburgh. The doubleheader is scheduled to begin at 5:35 p.m. ET.

Tickets dated for the April 15th postponed doubleheader are now good for the August 13th doubleheader. If fans holding tickets for April 15th do not wish to use them for the August 13th doubleheader, they can exchange those tickets for any remaining home game during the 2007 regular season, excluding Thursday, August 16, Friday, August 17 or Saturday, August 18, which are Skyblast dates.

Remembering Jackie: Due to the fact that their game was rained out on Jackie Robinson Day (April 15), the entire Pirates team will honor the Dodgers legend by wearing uniform No. 42 during the Friday, April 27 game with the Cincinnati Reds.

"We were kind of disappointed that we didn't get to take part in it the first time," Pirates pitcher Shawn Chacon said. "It's going to definitely be something special, and I'm surprised that they are doing it again for us. It will be something to be proud of."

Minor matters: Bryan Bullington allowed just two runs on seven hits while striking out four over six innings, as Triple-A Indianapolis registered an 8-3 win over Norfolk on Tuesday evening.

Bullington, who missed all of 2006 while recovering from right shoulder surgery, improved to 3-0 with the win. The 26-year-old right-hander was selected by the Pirates No. 1 overall in the 2002 First-Year Player Draft.

"Oh, it's going really good," Bullington stated. "I've had no setbacks with the shoulder since last July, and I feel like I'm getting stronger with each start. Everything feels great. I've been really pleased with my curveball, the slider's working and my fastball's got some good movement. I'm really pleased to get off to such a great start."

On deck: The Pirates wrap up their three-game series with the Astros with a 12:35 ET afternoon contest. Right-hander Tony Armas (0-2, 18.90) will be on the hill for the Bucs. Lefty Wandy Rodriquez (0-2, 4.74) will pitch for Houston.