Rosales hits pair of 2-run HRs, A's beat Cubs 12-6
Rosales homered off Jason Berken in the seventh for an 8-6 lead, then homered against Steve Perakilis to drive in the final two runs.
Chris Young hit a three-run homer in the first off Scott Baker, making his first start since elbow ligament-replacement surgery while with Minnesota last April 17. Baker got one out and gave up three hits and two walks.
Josh Donaldson had a three-run homer in the third against Cory Wade.
Chicago's Dave Sappelt had a solo homer in the second off Tommy Milone, who allowed four runs and eight hits in 4 2-3 innings. Brent Lillibridge added a two-run homer in the sixth against Hideki Okajima, tying the score 6-6.