DENVER -- Jhoulys Chacin was sailing along Friday night for Colorado Rockies, brushing aside the Arizona Diamondbacks' hitters with ease in the first game of their weekend series.
And the Rockies beat the Diamondbacks 3-1 for their seventh straight victory in large measure because of Chacin.
After three good starts this season, Chacin's fourth was his best until it suddenly ended. He held the Diamondbacks to three singles in 6 1/3 innings, walked one and struck out five before throwing his fourth pitch to Cody Ross, a 1-2 fastball, and then reaching for his lower left side.
He was diagnosed with left oblique stiffness and will be re-evaluated Saturday.
Rockies manager Walt Weiss, pitching coach Jim Wright and trainer Keith Dugger quickly went to the mound, and Chacin almost instantly walked to the dugout after throwing his 100th pitch.
Chacin, who was the Rockies' Opening Day starter and who lowered his ERA to 1.46, became Colorado's first starter to throw 100 pitches in a game since June 12, when former Rockies pitcher Jeremy Guthrie threw 102. The Rockies had gone 117 consecutive games without a starter throwing 100 pitches.
The win improved the Rockies' home record to 7-0, extending their franchise record for home wins to start a season.
Diamondbacks starter Ian Kennedy worked six innings and gave up three hits. Troy Tulowitzki hit a two-run homer in the fourth, and Chacin helped himself with a sacrifice fly, the first of his career, in the fifth.
Colorado's only other hits were a double by Michael Cuddyer and triple by Chris Nelson.
After Chacin left, Wilton Lopez struck out Ross and A.J. Pollock. Rex Brothers gave up a leadoff single to Didi Gregorious in the eighth but got Cliff Pennington to ground into a double play and retired pinch hitter Josh Wilson on a fly out.
Rafael Betancourt earned his sixth save but gave up an unearned run in the ninth when third baseman Nelson fielded Miguel Montero's grounder but made a low with two out that first baseman Todd Helton was unable to scoop out of the dirt.
On the play, Gerardo Parra scored. He led off the inning with a single and took second on defensive indifference while Montero was batting.
Kennedy retired the first 10 batters he faced, five on strikeouts, before Josh Rutledge walked with one out in the fourth. After Carlos Gonzalez struck out, Tulowitzki lined Kennedy's first-pitch fastball into the left-field stands for his fifth homer.
The Rockies have hit a home run in 14 of 16 games.
Cuddyer followed with a double on a grounder that hit third base, bounced high in the air and landed in short left field. Helton walked, but Kennedy got Wilin Rosario to ground into a fielder's choice.
Nelson led off the fifth with a triple, lining the ball over the head of center fielder Pollock, who broke late on it. Chacin extended Kennedy to eight pitches before hitting a sacrifice fly to center and giving the Rockies a 3-0 lead.
It was 52 degrees when the game started, practically balmy compared with 28 degrees on Thursday afternoon, tying the Rockies' franchise record for the lowest temperature at the beginning of a game.
NOTES: The Rockies recalled left-handed reliever Josh Outman from Colorado Springs and optioned reliever Chris Volstad to triple-A. The move gives Colorado a second left-hander in the bullpen along with Brothers. In five games at Colorado Springs, Outman went 1-0 with an 0.84 ERA and four walks and 14 strikeouts in 10 2/3 innings. Volstad pitched in four games for the Rockies with no record and an 8.53 ERA. He gave up one run in two innings Thursday against the Mets, the first time he pitched in eight days. Volstad was a starter before joining the Rockies this year and being shifted to relief. Manager Walt Weiss said it hasn't been decided whether Volstad will start at Colorado Springs or continue relieving. ... Left-hander Edwar Cabrera, who is on the Rockies' 60-day disabled list with a left shoulder impingement, threw batting practice for 10 minutes Friday at the Rockies' complex in Scottsdale, Ariz., for the first time since he was injured. Cabrera is scheduled to again throw batting practice Tuesday, Rockies trainer Keith Dugger said. Cabrera is not eligible to be activated until May 30. Cabrera will begin a rehabilitation assignment a month sooner if all goes well. Had he been healthy Cabrera would have started the season in the starting rotation at Colorado Springs. ... Cuddyer was back in the Rockies' lineup. After playing 19 innings in a doubleheader Tuesday, Cuddyer had tightness in both hamstrings Wednesday when the Rockies were snowed out. He said he felt fine Thursday, but as a precaution, Weiss scratched him from the lineup. ... The Diamondbacks played their third extra-inning game of the season on Thursday night and won it. They didn't get to their hotel in Denver until 4:30 a.m. MDT. Diamondbacks manager Kirk Gibson brushed aside anything to do with travel and the weather and said, "It's cold, we got in late, we didn't get the sleep we want, it's not an issue. It's part of the deal. We understand that going in. It's part of what we prepare for." ... Gregorious homered and doubled in his major-league debut on Thursday at Yankee Stadium. According to the Elias Sports Bureau, he is the seventh Arizona player to homer in his first at-bat with the Diamondbacks, the first to so on his first pitch and the fourth to hit his first career home run in his first at-bat for the Diamondbacks.