DENVER -- The Colorado Rockies continued their record rampage on Saturday night at Coors Field, thanks to an outstanding start by Jorge De La Rosa and some mistakes by the Arizona Diamondbacks.

With a 4-3 win, the Rockies improved to a franchise-best 8-0 at home to start a season and won their eighth straight game. The Rockies (13-4) have their best record in franchise history after 17 games and are tied with the Braves for the best record in the majors.

Rafael Betancourt survived a shaky ninth to pick up his seventh save.

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.

De La Rosa, who underwent Tommy John surgery in June 2011 and made three starts last September that were understandably spotty, has pitched 17 consecutive scoreless innings. During that span, he has allowed seven hits with five walks and 12 strikeouts.

The Diamondbacks hurt themselves with an error that led to the Rockies' first run and had two runners thrown out on the bases.

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 Diamondbacks manager Kirk Gibson moments later after he came out to argue the call.

Michael Cuddyer hit a home run for the Rockies in the sixth, belting Trevor Cahill's first-pitch curveball into the left-field stands.

After De La Rosa departed, Edgmer Escalona took the mound. He struck out two of the three batters he faced in the seventh but gave up a one-out single in the eighth followed by pinch-hitter Eric Chavez's two-run homer.

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 on the play. But Betancourt ended the game with his next pitch, getting Wil Nieves to fly out to right.

Eric Young Jr., whose drive to right center in the first was hauled in by Pollock in center just before he banged into the wall, led off the second with a triple over Pollock's head.

Cahill then hit Dexter Fowler on the right wrist with his 1-and-2 fastball, and Fowler stole second on the next pitch. Young scored and Fowler took third on Carlos Gonzalez's groundout. Troy Tulowitzki's sacrifice fly made it 3-0.

Early mistakes hurt the Diamondbacks. Nieves threw a ball past third base and down the left-field line, allowing Josh Rutledge to escape a rundown and score.

And the Diamondbacks had runners thrown out in successive innings. Pollock was caught stealing second to end the third. After Martin led off the fourth with a single, he tried to tag up on Paul Goldschmidt's fly to center and was thrown out at second on a relay that went 8-4-6.

Nieves' low throw came after Rutledge walked with one out in the second. Rutledge broke for second on Cahill's 1-and-0 pitch and kept running as Reid Brignac lined a single to right. Third base coach Stu Cole put up a late stop sign that Rutledge ran through, only to get caught in a rundown that Nieves botched.

De La Rosa needed 25 pitches to get through the first, when he faced just four batters, walking one and striking out two. But De La Rosa kept the Diamondbacks scoreless through five innings, becoming more efficient and throwing 68 pitches to that point.

NOTES: Rockies pitcher Jhoulys Chacin will miss his next scheduled start Wednesday against the Braves with what he thinks is a back injury and not an oblique issue. He left Friday after 6 1/3 scoreless innings and believes he is dealing with a back injury in the same area where he suffered back spasms in spring training. Chacin was scheduled to be examined Saturday by team doctor Tom Noonan and will undergo an MRI on Monday. Trainer Keith Dugger said of Chacin's injury: "It's up higher than an oblique typically." 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 Elias Sports Bureau. ... Rockies first baseman Todd Helton was not in the lineup because of a strained left forearm 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 lineup Saturday. Gibson said it was time to rest him. ... Outfielder Adam Eaton (strained left elbow) started throwing Friday. Gibson said he will throw every other day and has been a DH in extended spring games. When he is a couple weeks away 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 MRI showed fluid buildup in the muscle.