DENVER -- The Colorado Rockies continued their record rampage at Coors Field on Saturday night, thanks to an outstanding start by Jorge De La Rosa, early mistakes by the Arizona Diamondbacks and some small but vital contributions from the sluggers in the middle of the lineup.
With a 4-3 win, the Rockies improved to 8-0 at home, extending a franchise record at the start of a season, and won their eighth straight game.
The Rockies (13-4) have their best record in franchise history after 17 games. They are tied with the Braves for the best record in the majors.
Rafael Betancourt survived a shaky ninth to post his seventh save, giving up a run but getting Wil Nieves to fly out and strand runners at second and third.
De La Rosa held the Diamondbacks scoreless for six innings and allowed two singles, duplicating his pitching line from Sunday in San Diego when he also gave up two singles in six innings.
After undergoing Tommy John surgery in June 2011, De La Rosa made three starts last September that were understandably spotty but has pitched 17 consecutive scoreless innings this season. During that span, he has allowed seven hits with five walks and 12 strikeouts.
Asked if he is all the way back from the surgery, De La Rosa said, "That's in the past. I feel very good right now. I'm getting stronger every time."
De La Rosa only faced four batters in the first inning but threw 25 pitches. However, he only needed 57 pitches in his final five innings.
"I think we saw a lot of what we've been seeing from Jorge lately, commanding his secondary pitches," Rockies manager Walt Weiss said. "He's getting a lot of outs from his changeup and slider."
Weiss lifted De La Rosa after six innings because his spot in the lineup came up with two out in the sixth.
"I'm trying to balance the long haul," Weiss said. If we didn't get to his spot right there, I would've let him go back out. He was throwing really well. He'd have been fine running out there again, but I'm trying to protect our starters."
Michael Cuddyer homered in the sixth off Trevor Cahill for what proved to be the winning run. The Rockies scored an unearned run in the second and scored twice in the third, the runs driven in by Carlos Gonzalez on a groundout and Troy Tulowitzki on a sacrifice fly.
"We don't have to hit the long ball sometimes," Gonzalez said. "Sometimes all we got to do is that, just play smart. Like I say, every night it's somebody else ... and we continue to play good baseball."
The Diamondbacks hurt themselves with a throwing error in a rundown by Nieves that led to the Rockies' first run and they also had two runners thrown out on the bases.
"We didn't play a very good game early," Arizona manager Kirk Gibson said. "We made a couple errors, gave up an unearned run, made a couple outs on the bases. We had a shaky start, but Eric's home run definitely lifted us. We had a lot of pressure on but were unable to finish it out.
Eric Chavez hit a two-run, pinch-homer off Edgmer Escalona in the eighth. Weiss decided to leave Escalona in to face the left-handed hitting Chavez rather than bring on left-hander Rex Brothers, whom Weiss summoned after Chavez homer.
"If it's less than four runs, I probably would have (gone to Brothers against Chavez)," Weiss said. "I didn't feel bad about that matchup. I thought he had a chance to get a double play right there. Sinker-slider guy, he was throwing the ball real well."
Arizona's frustrations boiled over in the seventh when Cody Ross flipped his bat in the air after a called third strike by home-plate umpire Chad Fairchild. He ejected Ross immediately and Gibson moments later after he came out to argue the call.
"I thought it was a short fuse," Gibson said of Fairchild. "I think he threw me out shortly as well. But that's over with. We have a game to win tomorrow."
The third strike to Ross looked outside on a replay. Ross said he didn't say anything to Fairchild.
"I just took strike three and threw my bat and was walking out to the outfield," Ross said. "I heard a roar and I really didn't know what was going on, and I turned around and saw Gibby coming out.
"To be honest, I was frustrated with myself, with us, the way we've been not swinging the bats the last few games. It's just a lot of frustration. I didn't say anything. I didn't look at him. It was kind of bizarre."
Betancourt gave up a leadoff double to A.J. Pollock to start the ninth. Betancourt snared Martin Prado's hard bouncer for the first out, but Pollock moved to third on Paul Goldschmidt's single.
Betancourt was ahead of Gerardo Parra 1-and-2 but walked him to load the bases. He got pinch-hitter Miguel Montero, who had 14 homers at Coors Field in his previous 218 at-bats, to ground out to Cuddyer at first base, with a run scoring. But Betancourt, who has converted his seven save opportunities, ended the game with his next pitch.
Notes: Rockies pitcher Jhoulys Chacin will miss his next scheduled start Wednesday against the Braves. He left Friday after 6 1/3 scoreless innings but was "way better than yesterday" and believes he is dealing with a back injury in the same area that he suffered back spasms in spring training and not an injury to his left oblique. Chacin was examined Saturday by Dr. Tom Noonan, the Rockies' medical director, and will undergo an MRI on Monday. Chacin said Noonan told the pitcher he does not have an oblique injury and is dealing with back soreness. Chacin has a 1.46 ERA, the third lowest by a Rockies starter in four starts. Ubaldo Jimenez had an 0.95 ERA in 2010 and Shawn Chacon had an 0.98 ERA in 2003 after four starts, according to the Elias Sports Bureau. ... Rockies first baseman Todd Helton was not in the lineup because of a strained left forearm he suffered on a swing Tuesday in the first game of a doubleheader against the Mets. He said he expected the soreness to go away after a couple days, but it had not. "It's feeling pretty good right now," Helton said before Saturday's game. "I've never done anything like it. I could play right now if I had to, I guess." ... Parra, who had played every inning of Arizona's first 16 games, three of which went extra innings, was not in the Arizona lineup. Gibson said it was time to rest him. ... Outfielder Adam Eaton (strained left elbow) started throwing Friday. Gibson said Eaton will throw every other day and has been a DH in extended spring games. When he is a couple weeks from returning to the Diamondbacks, Gibson said Eaton will go to Reno and DH. ... Diamondbacks outfielder Jason Kubel is in "calm-down mode" just doing mobility exercises, Gibson said. Kubel went on the disabled list April 13 with a strained left quadriceps and an underwent an MRI that showed fluid in the muscle.