Right-hander A.J. Burnett, who held the Cubs hitless for 7 2/3 innings on July 31 in Chicago and wound up with a one-hit shutout, gets the ball for the Pirates.
At 15-5, Burnett has a chance to win 20 games for the first time in his career by the end of this season. He hasn't thought about that possibility with the Pirates trying to climb into the postseason.
"It doesn't matter if I win 20, 19, 18 or whatever," Burnett said. "I'm just trying to win ballgames for this club; that's all I try to do every time. A win for me just means the team is one game closer to our goal."
He allowed two runs on two hits in 6 2/3 innings against the Brewers in his last start. He hasn't given up a run to the Cubs in either of his starts against them this season (14 1/3 innings).
Left-hander Travis Wood takes the mound for the Cubs, and he will be looking for his first win since July 6. He is 0-8 in his last 10 starts, though he's pitched well in each of his last three.
In his most recent outing Sunday against the Giants, Wood exited the game with a 5-3 lead in the sixth inning. The bullpen couldn't hold the lead, however, and the southpaw settled for a no-decision in the eventual 7-5 loss.
"He's positioned himself as one of our starters [for 2013]," manager Dale Sveum said. "He's made strides to learn how to pitch completely different than he ever has, and it's made him able to survive and have some really good games. ... He's coming, and it's been an adjustment, but I think he's done a pretty good job, too."
Against the Pirates on Aug. 1, Wood allowed two runs over five innings while striking out six, but took the loss in an 8-4 Pittsburgh victory.
Cubs: Fiery finale leads to ejections
A pair of bench-clearing incidents in the Cubs' series finale in Washington on Thursday led to the ejections of pitcher Manuel Corpas and catcher Steve Clevenger.
The ejections came in the sixth inning after the benches cleared following Corpas' inside pitch to Bryce Harper. The benches had already cleared one inning earlier after Cubs bench coach Jamie Quirk exchanged words with Nationals third-base coach Bo Porter. Quirk was subsequently ejected.
It wasn't immediately clear if any of the ejections will result in suspensions.
Pirates: Walker not ready to return
Neil Walker's tight lower back isn't bothering him while he does daily activities like tying his shoes, but the second baseman doesn't feel ready to play baseball yet.
"The last couple of days, we pushed the envelope a little more, in terms of throwing and moving laterally, so [we'll] see how far we can go," said Walker, who missed his ninth straight game Wednesday. "My body had responded very well, but when you start torquing ... I don't want to go out and take a cut at a 95-mph fastball when I'm not ready."
He is doubtful to return for this weekend's series against the Cubs.
"We're on the outside looking in on that," Pirates manager Clint Hurdle said. "He tried swinging the bat once and had to back away."
Burnett is 6-0 with a 2.78 ERA in seven career starts against the Cubs.
Cubs outfielder Alfonso Soriano is 3-for-19 (.158) with nine strikeouts in his career against Burnett. The nine strikeouts are the most Soriano has against any pitcher whom he's faced fewer than 25 times.
This is the latest in the season the Pirates have been above .500 since 1992, the last year they posted a winning record.