DENVER (AP) -- Ryan Spilborghs desperately wanted a chance at redemption. With the Colorado Rockies looking at a heartbreaking loss, he got his shot and didn't waste it.
Spilborghs hit a grand slam in the bottom of the 14th inning, giving the Rockies a come-from-behind 6-4 victory over the San Francisco Giants on Monday night.
Spilborghs couldn't deliver with men on base in the 10th inning, grounding into a double play with a man on third. In the top of the 14th, he misread the carom off the wall on Edgar Renteria 's triple that started the Giants' three-run rally.
That was on his mind when the Rockies came to bat in the bottom of the inning.
''I had a chance off (Brian) Wilson and missed my opportunity,'' Spilborghs said. ''And then I felt like I missed the ball with Renteria and he got a triple. I was almost shaking because I wanted a chance to redeem myself.''
Spilborghs jumped on reliever Merkin Valdez 's 96-mph fastball and sent it into the Colorado bullpen to give the Rockies the dramatic win.
''When I was running the bases I was trying to get to my teammates as fast as I could,'' Spilborghs said.
Colorado won the final three games of the four-game series and opened a four-game lead over the Giants in the NL wild-card race.
''It's a two-game swing,'' Rockies manager Jim Tracy said. ''They're looking like they're going out of here two back and now they're going home four. That's absolutely huge.''
The Giants had taken a 4-1 lead in the top of the 14th on Eugenio Velez 's two-run triple and Juan Uribe 's groundout.
''I thought I had won the game at the time,'' Velez said. ''I thought we had it won.''
But Brandon Medders walked Dexter Fowler leading off the bottom half. One out later Justin Miller (2-3) relieved and gave up a one-out single to pinch-hitter Chris Iannetta . He then walked Troy Tulowitzki and Adam Eaton to make it 4-2.
Before he stepped in the batter's box Tracy told Eaton to keep the bat on his shoulder.
''I told him not to swing,'' Tracy said. ''Even if Miller threw three balls down the Middle, take the strikeout because I wanted Spilly to get a chance to hit.''
Valdez, the Giants eighth pitcher, came on and Spilborghs homered on a 0-1 pitch.
''No question it was a tough loss,'' Giants manager Bruce Bochy said. ''You are going to have ups and downs, but this was as tough a loss as you can have.''
Eaton (1-0) worked the final two innings to get the win. He gave up three runs and walked five.
The Rockies had chances in the 10th and 11th innings but couldn't come up with the big hit. Spilborghs grounded into a double play to end the 10th and Clint Barmes flew out to center to end the 11th with runners on first and third.
The Giants loaded the bases with two outs in the 13th but Medders lined out to third to end the inning.
''This was the most bizarre game I've ever been involved in,'' Medders said. ''To go that long and to go ahead by three runs and to lose on a grand slam was just bizarre.''
Colorado starter Jason Marquis , trying to become the first pitcher in the NL to win 15 games, went eight innings, giving up one run on six hits. He struck out five and walked two.
San Francisco starter Barry Zito didn't give up a hit until Brad Hawpe 's two-out single to right in the fourth. Then the Rockies broke through in the fifth.
Ian Stewart led off with a walk and Yorvit Torrealba reached on an error by third baseman Uribe. Marquis sacrificed the runners up a base, but Stewart was tagged out in a rundown on Fowler's grounder to short.
With two outs, Zito issued consecutive walks to Barmes and Todd Helton to make it 1-all. Tulowitzki flew out to deep right to end the inning.
The Giants took a 1-0 lead in first when Velez led off with a double, stole second, moved to third on Randy Winn 's fly to left and scored on Pablo Sandoval 's sacrifice fly to center.
NOTES: Sandoval left the game in the third inning with a tight right calf. ... An MRI on Rockies' RHP Aaron Cook 's right shoulder revealed no damage to the joint. Cook, who was placed on the 15-day DL on Saturday with a strained shoulder, will start throwing after Colorado's three-game series in San Francisco this weekend. ... Giants 2B Freddy Sanchez sat out his seventh straight game with a sore left shoulder.