DENVER (AP) - Hunter Pence hit one of San Francisco's three solo homers and reliever Yusmeiro Petit threw three sharp innings after starter Matt Cain left with a strained right hamstring as the Giants beat the Colorado Rockies 5-1 on Wednesday night.
Pablo Sandoval and Brandon Crawford also connected for the NL West-leading Giants, who won at Coors Field for just the fifth time in 15 games dating back to last season.
Cain didn't allow a hit through three innings, before giving way to Petit (3-1). He and four other relievers limited the best offensive team in the majors to just five hits.
Jhoulys Chacin (0-3) worked 5 2-3 innings and allowed three runs, including a homer to Pence in the fourth and another to Sandoval two innings later.
Giants key setup reliever Santiago Casilla also suffered a right hamstring strain, but looked to be far worse pain than Cain was. Casilla made a rare plate appearance in the ninth inning, so that he could close out the game in a non-save situation. He grounded out to shortstop, however Casilla tried to beat the throw and fell face-first just past first base.
Casilla is scheduled for an MRI on Thursday.