PHOENIX — Colorado left-hander Drew Pomeranz worked himself back to the majors, believing he had straightened himself and his mechanics out.
After a second straight shaky outing, it's clear he still has some work to do.
Pomeranz struggled in his second start since being called up, allowing five runs in the first three innings to give the Arizona Diamondbacks all the momentum they needed for an 11-1 victory over the Rockies on Saturday night.
"I feel like I have worked on a lot of things this year and have gotten better and haven't been throwing like this," Pomeranz said. "So it's something that I need to figure out and give us a better chance to win the game."
Pomeranz, who made 22 starts for Colorado last season, spent most of this year at Triple-A Colorado Springs before being called up to pitch against San Francisco on Sunday. He allowed four runs on seven hits — two of those homers — in 4 1-3 innings of a 5-2 loss.
The left-hander labored from the start against Arizona, needing 10 pitches to get leadoff hitter A.J. Pollock and going over 40 the first two innings. He walked two to load the bases in the second inning and pitcher Wade Miley followed with his fourth hit of the season, a three-run double slapped into the corner in left.
Pomeranz opened the third inning with a walk, then left a letter-high fastball up to Paul Goldschmidt, who hit it into the second deck in left for a two-run homer that put Arizona up 5-0 and increased his NL-leading RBI total to 73.
Pomeranz (0-2) worked out of a bases-loaded jam in the fourth inning after walking Goldschmidt, but was lifted after that. He allowed five runs on five hits and walked five to lose for the seventh time in eight decisions dating to last season.
"I have seen him pretty good and I know that is in there, but you've got to make some progress and be more efficient," said Rockies manager Walt Weiss, whose team has lost five of six.
Arizona starter Wade Miley certainly was — with his arm and his bat.
The Diamondbacks returned to the desert on Friday after a 10-game road trip that ended with a long series against the Mets that included rain delays and two games that each lasted at least 15 innings.
Arizona beat Colorado 5-0 in the opener behind Tyler Skaggs' eight scoreless innings and jumped on Pomeranz early in the second game.
Miley got it started his double in the second inning and Goldschmidt, named to the NL All-Star team earlier in the day, hit his 21st homer in the third.
The Diamondbacks poured it on after that, adding a three-run homer by Miguel Montero and a two-run shot by Martin Prado. Cody Ross tied a team record and set a career high with five of Arizona's 12 hits and scored three runs.
That gave Miley (5-7) the leeway to work around the edges of the plate, giving the Rockies few good pitches while sending the NL West-leading Diamondbacks to their fourth straight win.
"The bullpen got used a lot in New York with all those (extra-inning) games and I was just trying to extend it, just go as long as you can to give them a break," Miley said. "It was good."
The Rockies had four baserunners in the series opener and were only marginally better against Miley.
All-Star Carlos Gonzalez hit his NL-leading 24th homer and had four hits after missing Friday's game with a sore back, but the rest of the Rockies went 2 for 26, including 0 for 7 with runners in scoring position.
"I don't know what the numbers are but it seemed like he went strike one with just about every batter," Weiss said. "It is a lot easier to pitch that way. When you are 0-1 there are a lot more options that way and that is what he did."
Notes: Ross became the 16th player in Arizona history with five hits, the first since Aaron Hill on Sept. 4, 2012, against San Francisco. ... The Diamondbacks had an extra-base hit in their 71st straight game, matching the sixth-longest streak in team history (2006). ... Colorado's Michael Cuddyer had a double in the seventh inning to extend his road hitting streak to 15 games. ... Arizona LHP Patrick Corbin will make his seventh attempt at reaching 10 wins against the Rockies on Sunday. The All-Star is 0-1 over his last six starts. ... RHP Roy Oswalt will try for his first win since signing with the Rockies in May in the series finale against Arizona. He's made three starts since being called up, going 0-3 with a 7.88 ERA.