SAN FRANCISCO -- Trevor Story had no idea he was sparking a record-setting effort when he led off the fifth inning with a home run.
Story and Nolan Arenado each homered and drove in three runs, and the Colorado Rockies set a franchise record with their 13-run inning in a 17-7 victory over the San Francisco Giants on Thursday night.
"I was looking to start off the inning by getting on base," Story said. "I happened to hit a home run. Innings like that are always fun."
He also doubled in a run the next time he came to the plate.
Gerardo Parra had two hits and three RBI in the fifth, when Colorado sent 17 batters to the plate.
It's the most runs scored in an inning by any team since Arizona scored 13 in the fourth against Pittsburgh on April 11, 2010.
"It's very surprising," Arenado said. "You never see that here. They have a playoff team and good pitching."
Every Rockies hitter either scored or drove in a run in the inning, including starting pitcher Chris Rusin, who singled home a pair of runs. Seven of the nine did both.
"The last three games we had trouble scoring," Rockies manager Walt Weiss said. "You can't predict these kind of games. The approach was good all night."
Matt Cain (0-4) lost his first four decisions in a season for the first time in his career. He allowed eight runs on 10 hits in four-plus innings and did not walk a batter or strike out anyone. Reliever Vin Mazzaro yielded nine runs on six hits while recording just one out.
"The location wasn't bad; the balls were a little higher than they needed to be," Cain said. "With a group of guys who can swing the bat as well as they can, they will take advantage."
D.J. LeMahieu collected three hits and drove in a run, Tony Wolters drove in two runs and the Rockies won their fifth in seven games following a season-worst, five-game losing streak. Mark Reynolds also had a pair of RBI.
Rusin had a 14 2/3 innings scoreless streak come to an end, though Colorado's big fifth made it a moot point.
Rusin gave up seven runs on 13 hits in his 4 1/3 innings. He walked two and struck out four. Despite leaving with a 10-run advantage, he was not eligible for the win because he failed to finish the fifth.
The Giants rallied for four runs in the bottom of the fifth, with Rusin taken out after giving up a two-run single to Gregor Blanco.
Christian Bergman (1-3) came on to throw 2 2/3 scoreless innings, striking out three, to get credit for the win.
Rockies: LHP Jorge De La Rosa (groin) will throw a bullpen session at the Rockies' spring training facilities in Scottsdale. If all goes well he will begin a rehab assignment Monday. ... IF Danny Descalso (left hand) had three hits in six at-bats in an extended spring training game Thursday. He's scheduled to play in the field on Friday. ... RHP Jason Motte (right shoulder strain) will face hitters before Friday's game in San Francisco.
Giants: IF Joe Panik (groin) may return to the starting lineup as early as Friday, a week after tweaking his groin in a game against the New York Mets. He was expected to test the injury in batting practice. ... OF Hunter Pence was held out of the lineup with tightness in his back and should return Friday. ... RHP George Kontos is scheduled for a rehab appearance with Triple-A Sacramento on Sunday. ... RHP Sergio Romo has been playing long toss from 90 feet and will throw from the mound on Monday.
Rockies: RHP Chad Bettis gets the call Friday night. He's 2-0 on the road and beat the Giants in his only start at AT&T Park last June 26.
Giants: LHP Madison Bumgarner (3-2, 3.03) takes the mound Friday. He's 4-1 with a 3.44 ERA over his last seven starts against the Rockies.
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