Lake’s two-run homer off Tyler Skaggs with no outs in the fifth inning gave the Cubs a 3-0 lead. Lake’s RBI single in the ninth scored Darwin Barney with an insurance run.
Dioner Navarro hit a solo home run in the second for the Cubs.
The loss, coupled with the Los Angeles Dodgers’ win in Toronto on Monday night, dropped the Diamondbacks out of first place in NL West. They held or shared the division’s top spot since May 15. Arizona have lost four of their past five.
Chris Rusin (1-0) got the win, while Kevin Gregg pitched the ninth for his 19th save.
Skaggs (2-2) took the loss.
REDS 11, GIANTS 0
In San Francisco, Bronson Arroyo pitched a seven-hitter for his sixth career shutout, beating Tim Lincecum and San Francisco for his first victory at AT&T Park and No. 100 with Cincinnati.
Arroyo (9-7) struck out six and did not walk a batter in his 15th career complete game, a 108-pitch gem that ended in 2 hours, 45 minutes. Derrick Robinson ended it with a tough catch in deep center.
Devin Mesoraco and Shin-Soo Choo homered in the second inning off Lincecum, pitching for the first time since his no-hitter at San Diego.
Jay Bruce also hit a solo homer, Todd Frazier added a three-run double and Robinson, a late addition to the lineup, had three hits.