PHOENIX -- Blowing leads has been an uncomfortable trait of the Colorado Rockies lately.
They did it again Saturday night, only this time, they came back in a hurry and went on to pound the Arizona Diamondbacks 10-4 and open a little breathing space in their wild-card race.
The victory, combined with San Francisco's 12-1 loss at Los Angeles, extended Colorado's wild-card lead over the Giants to 3 1/2 games. Florida remained four behind and Atlanta 4 1/2 back.
"It's awesome. It's what you dream about," Giambi said of being in a playoff race after joining the Rockies on Sept. 1. "I keep telling people when I decided to come over here that this is the fun part of the game, to have something to play for in September."
The Rockies matched a franchise record with their 39th road victory, but they know they probably win or lose a playoff spot in their comfortable surroundings in Denver.
"We're 3-5 on this road trip," manager Jim Tracy said, "and we have nine of our final 13 games at Coors."
That nine-game home stand starts Tuesday, after Colorado wraps up this trip with a game against Arizona ace Dan Haren on Sunday.
Tulowitzki and Carlos Gonzalez hit solo home runs in the first inning, and the Rockies entered the ninth clinging to a 5-4 lead. That's when Colorado blew it open with five runs, three of them thanks to Giambi's pinch-hit home run.
Ryan Spilborgh drove in two runs for Colorado with a pinch-hit single in the seventh and a double in the ninth.
Hammel (9-8), whose last victory came Aug. 20 at Washington, allowed three runs on four hits in seven innings, striking out five and walking two. He has suffered from a lack of run support in the recent past.
"He's been much better than a 9-8 pitcher for us," Tracy said.
The Rockies scored the go-ahead run on left fielder Gerardo Parra's throwing error in the fourth. Spilborghs' pinch-hit single made it 5-3 in the seventh.
Arizona cut it to 5-4 in the eighth when Stephen Drew hit his 11th triple, tying him for the major league-lead, then scored on Upton's sacrifice fly. Colorado put it away with five runs in the ninth. Giambi's fourth career pinch-hit homer came on the first pitch from reliever Scott Schoeneweis.
Parra made a nice running catch of Ian Stewart's fly ball, but an ill-advised attempt to throw the runner out at home sailed over the head of catcher Miguel Montero, allowing a second run to score on the play to put Colorado up for good 4-3.
Arizona briefly took the lead in the third.
Scherzer and Chris Young singled to start the inning. After Drew struck out, Upton hit the first pitch from Hammel some 424 feet to left-center for his 25th home run.
"My mindset after that was that's all they get," Hammel said. "I made a bad pitch and paid for it. As a starting pitcher, you've got give that one up. I gave up the lead but these guys will come through with runs. We've got a good-hitting ball club."
In the first, Gonzalez lined Scherzer's 2-0 pitch over the left field wall for his second leadoff home run of the season, then -- after two outs -- Tulowitzki hit the first pitch he saw into the seats in left to make it 2-0.
Scherzer allowed three hits but walked five and hit a batter in 5 1/3 innings.
"I wasn't able to get ahead of hitters," he said, "and that's what cost me there with walking five guys. Walks will always kill you."
Arizona 3B Mark Reynolds struck out twice to give him 202 for the season, two shy of the major league record he set last year. ... Colorado 1B Todd Helton was back in the lineup despite taking a nasty shot in the left shin from a foul ball by Gonzalez Friday night. Helton broke an 0-for-15 slump with a single in the ninth. ... Arizona RHP Dan Haren goes for his 15th victory on Sunday.