Adam Frazier and Ke'Bryan Hayes homered back-to-back to lead off the first inning and the Pirates held on to edge the Cubs 2-1 in Pittsburgh.
Trevor Williams gave up a first-inning homer to Anthony Rizzo, but allowed just two more hits over five-and-two-thirds for his second win.
Richard Rodriguez notched his fourth save. Kyle Hendricks pitched into the eighth, but took the tough-luck loss.
The playoff-bound Cubs are 32-and-24.
(Photo by Justin Berl/Getty Images)