Denver, CO (Best E Casino) - Stephen Drew hit the go-ahead two-run homer in the top of the ninth to lift the Arizona Diamondbacks to an all-important 5-3 win over the Colorado Rockies at Coors Field.

Drew finished the game 2-for-5 with two runs scored while Chad Tracy went 2- for-4 with an RBI for the Diamondbacks, who have won five of six.

Doug Davis hurled a crucial quality start for Arizona, as he gave up two runs on six hits and a walk, with four strikeouts. Tony Pena (3-2) got the win despite giving up the lead in the eighth. Chad Qualls got his sixth save of the season after pitching a scoreless ninth inning.

The D-Backs remain 3 1/2 games behind the NL West-leading Dodgers, who defeated the Giants on Saturday.

Troy Tulowitzki went 3-for-5 with a pair of runs scored, and Jeff Baker homered and drove in two runs for the Rockies, who snapped a three-game winning streak.

Aaron Cook went 6 1/3 innings and allowed three runs -- two earned -- on five hits and three walks while fanning four. Brian Fuentes (1-5) took the loss after giving up the homer to Drew in the ninth.

Fuentes started the ninth for the Rockies. Chris Young worked a leadoff walk and stole second two outs later. Then Drew launched an offering into the right-field seats, giving the Diamondbacks a 5-3 lead.

"Honest to say, I didn't think it was going to go out," Drew said. "I thought it might it hit the top of the wall 'cause I saw Baker runnin'. It was just a great feeling to see it go out."

The game would not be won easily, however, as the Rockies put together a rally in the home ninth off Qualls. With one out, Ian Stewart blasted a triple to the gap in right-center. Brad Hawpe struck out, but Joe Koshansky walked to bring the go-ahead run to the plate in Tulowitzki, who flied out to end the game.

The Diamondbacks got on the board in the first. Drew hit a leadoff double and, one out later, Tracy hit an RBI double to make it 1-0. Arizona loaded the bases wit nobody out in the second, but Davis hit into a double play, scoring a run but ending the threat.

Colorado cut the deficit to one in the fourth. Tulowitzki led off with a single and moved to third on Ryan Spilborghs ground-rule double. One out later, Chris Iannetta walked to load the bases. Baker then came up and singled to center to drive in a run.

Baker tied the game at two in the sixth, hitting a 1-1 pitch off Davis into the seats for his 11th homer of the year.

Arizona went back in front in the seventh. Chris Snyder and Augie Ojeda both walked, and, with one out, pinch-hitter Tony Clark hit a ball to center that Willy Taveras couldn't field in center, allowing Snyder to score.

"He sprinted so hard running back to the wall, he just ended up overrunning it," Colorado manager Clint Hurdle said of Taveras' fielding gaffe. "Willy's done a fine job all season running down balls."

Tulowitzki hit a leadoff double in the bottom of the eighth, moved to third on Spilborghs' groundball and scored on Garrett Atkins' sacrifice fly, tying the game at three.

Game Notes

The Diamondbacks lead the season series 11-3...Drew's homer was his 19th of the season. He also added his 40th double in the game...Arizona left six runners on base while the Rockies left eight.