Carlos Zambrano returned to the rotation Friday night against the Astros, making his first start since April 20. Zambrano had switched to the bullpen after four starts and made 13 relief appearances before being moved back into the rotation.
Ryan Dempster (3-5, 3.72 ERA) and Wells (3-3, 4.40 ERA) will finish the Cubs' series against the Astros on Saturday and Sunday, respectively.
Carlos Silva (7-0, 3.12 ERA) will start the makeup game Monday in Pittsburgh. This will give the right-hander an extended break. His last start was May 29 against the Cardinals, when he threw seven shutout innings, giving up two hits in a 5-0 win.
"It gives [Silva] a little time, a little rest," Cubs manager Lou Piniella said. "Also, we would've had to pitch Wells back to back against [the Pirates]. We didn't want to come right back with Wells, who had just pitched against them."
Wells pitched in Pittsburgh on May 31. In that game, he threw five shutout innings, giving up three hits and walking three. He did not get a decision. Wells is 0-1 in two starts against the Pirates.
Lilly (1-5, 3.61 ERA) is 0-2 in three starts against the Pirates this season, and he will open the Cubs' series against the Brewers on Tuesday.