DENVER -- Pitching at Coors Field was no big deal to Ian Snell.
"It doesn't matter about what kind of ballpark or if the ball flies. I pitch the same. I think the same," Snell said.
Snell (6-3) worked both sides of the plate brilliantly with his 96 mph fastball, deceptive changeup and sharp slider. He allowed two earned runs and six hits in 6 1/3 innings for the Pirates, who improved the majors' worst road record to 5-22 and extended the Rockies' losing streak to a season-high six games.
Colorado, which was swept by Florida over the weekend, has been outscored 26-7 in its four consecutive losses at Coors Field to the two worst teams in the National League, during which it's never had the lead.
Snell struck out six in the first three innings, when he threw 29 of 35 pitches for strikes.
"I know he's pitched some good games, but up to this point in the season, I don't know if he's pitched a better one that this one," Pirates manager Jim Tracy said.
Just 28 of his 94 pitches missed the strike zone and Snell walked just one of the 25 batters he faced.
"I always have great command," Snell said. "It doesn't matter if it is here or anywhere."
Pittsburgh's confident 24-year-old kept confusing Colorado's lineup inning after impressive inning.
"I kept them off balance. I could tell a lot of them were late on fastballs. They were fouling them off. Once you see that it sets them up for other pitches," Snell said. "I set them up pretty good where if they chased one breaking ball, they were going to chase another one."
Aaron Cook (5-6) allowed 10 hits and five runs in six-plus innings.
"One of those games, wash it off and do better next time," Cook said.
Colorado pulled to 5-2 on pinch-hitter Ryan Spilborghs' run-scoring single in the bottom half of the seventh, but the Rockies went 1-for-8 the rest of the way. Mike Gonzalez pitched the ninth for his eighth save in eight chances.
The Rockies have dropped 11 of 13, the primary culprit being an inability to connect in the clutch, which has left the pitching staff with hardly any wiggle room. Colorado has gone 2-for-36 with runners in scoring position during the six-game skid.
"We don't point fingers," said Rockies slugger Todd Helton, who had his first multihit game since May 16. "We haven't had good at-bats like we're capable of doing. It's frustrating. We're just not being consistent at the plate. It happens and we're still a good team. We need to score more runs. Pitching's still there."
Omar Quintanilla, who struck out three times against Snell and grounded into a double play to kill a seventh-inning rally, got the start at second base for the Rockies one day after his call-up from Triple-A Colorado Springs and was tested right away.
He missed a diving stab at Jason Bay's first-inning bloop single that landed in the grass in shallow right field to drive in a run.
With left-handers Paul Maholm and Oliver Perez coming up, leadoff hitter Jamey Carroll will return to the lineup at second base for the remainder of the series, Colorado manager Clint Hurdle said.
Helton said the Rockies are confident they'll recover from their offensive funk before this develops into a summer-long swoon.
"Each guy's different," Helton said. "Some guys who struggle (have) to swing their way out of it and other guys have got to slow down and work the count a little bit."
Snell's previous career high in strikeouts was nine, set May 3 against the New York Mets. ... The Pirates placed C Ryan Doumit on the 15-day DL with a torn left hamstring that could sideline him up for to two months. They recalled utility player Yurendell DeCaster from Triple-A Indianapolis. ... Helton went 2-for-4.