Mark DeRosa doubled and drove in a run, and Reed Johnson hit a tiebreaking single in a three-run fourth inning as Chicago sent the Pirates to their third straight loss.
Hill (1-0) combined with four relievers on a six-hitter, allowing one run, three hits and three walks in five innings with four strikeouts. Jon Lieber, Sean Marshall, Carlos Marmol and Kerry Wood followed, with Wood pitching a perfect ninth for his fourth save in five chances.
DeRosa, who doubled leading off the second and singled in the tying run, is batting .321. His good start followed a difficult spring training in which he got the flu, doctors performed a procedure to cure an irregular heartbeat, and the Cubs discussed replacing him with Baltimore's Brian Roberts.
Ian Snell (2-1) lost for the first time in seven starts since Sept. 8 - also against the Cubs. He gave up three runs and nine hits in six innings, striking out five and walking one.
Pittsburgh's Nate McLouth hit a solo home run off Marmol in the eighth to extend his season-opening hitting streak to 16 games. The Pirates put two more runners on, but Marmol fanned Adam LaRoche for his fifth strikeout. Marmol had struck out the side in the seventh.
Xavier Nady hit an RBI single in the second and held at third on Jose Bautista's two-out double off the left-field wall. Hill the struck out Snell.
Kosuke Fukudome tripled leading off the fourth and scored on DeRosa's single. After Johnson's go-ahead infield single, rookie Eric Patterson hit an RBI groundout.
Notes:@ Cubs manager Lou Piniella, who managed at Cincinnati in the early
'90s, didn't agree with Reds broadcaster Marty Brennaman, who said Cubs fans were "obnoxious" for, among other things, littering the field with batting-practice baseballs after Adam Dunn homered at Wrigley earlier in the week. "I don't think our fans are obnoxious. I think they get into the ballgame," Piniella said.
