The Pirates snapped an ugly 17-game skid as the visitor in the opener of the set on Monday when Jose Tabata doubled in the go-ahead run in the ninth inning, as Pittsburgh took a hard-fought 2-1 victory.
The Pirates had not won away from home since May 25 at Cincinnati and had also lost six in a row overall. Pittsburgh still has the NL's worst record but are a more than solid 8-2 against the Cubs this season and have won three of four at Wrigley.
Paul Maholm (5-6) was excellent in helping Pittsburgh capture the win on Monday, giving up just one run on seven hits in eight innings. He did not walk a batter and struck out two as he rebounded from his start last Wednesday, when he allowed seven runs (five earned) in one inning against Texas.
"I was looking forward to it," Maholm said of the start. "The last one I put behind me the next day and got prepared for these guys and stayed in my routine. Nothing changed. I don't expect to have very many of those one-inning outings. So I came out tonight and everything worked, and defense made some great plays and I got ahead and kept the ball down."
Octavio Dotel pitched a scoreless ninth for his 15th save.
Andrew Cashner (0-2) allowed the go-ahead run to reach base and took the loss for the Cubs, who were coming off Sunday's win over the White Sox.
Randy Wells was solid, allowing just a run on three hits and four walks while fanning six in six innings of work on Monday.
"I think from a team standpoint, everyone in here wants to win and they want to win bad," said Cubs second baseman Ryan Theriot. "And that's a great point; it may be you're putting a little bit too much pressure on. Everyone wants to be that guy. That could be it."
Chicago, which has not won back-to-back games since June 16-17, also officially announced it will place pitcher Carlos Zambrano on the restricted list Tuesday following a heated exchange with teammate Derrek Lee in the Cubs' dugout last Friday against the White Sox.
Zambrano was ordered to undergo evaluation for anger issues and will be sidelined until after the All-Star break.
"Hopefully he goes and gets the help he needs and can rectify some of his actions with his teammates and be able to move forward after the break," general manager Jim Hendry said. "We've obviously had a lot of transgressions in the past with Carlos. So I think we all agree it's time he got help and then maybe address the apologies later."
Hard-luck lefty Ted Lilly will head to the hill tonight for the Cubs. Lilly has a poor record at 2-6 but a solid 3.20 earned run average this season. The southpaw is 0-2 with a 4.35 ERA in three starts against the Pirates this season but Chicago has managed to score just four runs in those losses.
The Pirates will counter with right-hander Jeff Karstens. The right-hander is coming off a no-decision in his last outing, giving up three runs in 5 1/3 innings during a 6-5 loss at Texas and is 2-1 with a 4.05 ERA in four career starts versus the Cubs.