Wilmer Flores hit a go-ahead, two-run homer off closer Kenley Jansen in the ninth inning and the San Francisco Giants rallied past the Los Angeles Dodgers 4-2 on Wednesday night. Mike Yastrzemski homered early to help the Giants regain a two-game lead in the NL West over the defending World Series champions. San Francisco has won two of three in a four-game series between the longtime rivals that wraps up Thursday night.