DENVER -- After winning their past three games by scoring the deciding run in the eighth inning or later, the Colorado Rockies were able to breathe considerably easier Saturday night.

They ripped Philadelphia Phillies rookie starter Nick Pivetta for five runs in the first, scored three more in the third and cruised to an 8-5 victory. The win was the fourth in five games for the Rockies on their homestand, which ends Sunday.

The Phillies have lost five straight on their eight-game road trip. They have scored eight runs in two losses at Coors Field and 13 during their five-game skid.

Rockies starter Jon Gray (4-2) remained unbeaten at Coors Field this season after allowing one run on six hits in seven innings with one walk and four strikeouts. In four home starts, Gray is 3-0 with a 3.00 ERA. He has surrendered four walks in 25 innings in his past four starts with 25 strikeouts.

He broke a two-start losing streak but was coming off an outing Sunday at Washington where he allowed three runs and four hits with one walk and eight strikeouts in seven innings.

"These are two good back-to-back games for Jon," Rockies manager Bud Black said. "The last two are indicative of what I think Jon can do -- seven innings, in control. We got him some runs early. He continued to pitch aggressively with the fastball, which I liked. It looked as though the fastball command was very good."

The Rockies batted around in the first against Pivetta (4-7) and drove him from the game after a career low-tying 2 2/3 innings. The final batter he faced was Pat Valaika, who hit a two-run homer and finished with three RBIs.

Pivetta needed 42 pitches to complete the first. Charlie Blackmon led off with a walk and Pivetta hit DJ LeMahieu with a 3-2 fastball before Nolan Arenado singled to load the bases.

Gerardo Parra singled home two runs. Mark Reynolds grounded into a run-scoring fielder's choice and went to third on first baseman Tommy Joseph's two-base error when he moved left for Carlos Gonzalez's grounder that bounced over his glove. A sacrifice fly by Jonathan Lucroy and Valaika's RBI single completed the scoring.

"I didn't make pitches all night tonight," Pivetta said. "I left balls in the middle. In Colorado when you're facing a lineup like that, it's not going to be good. They really didn't put that great of swings on pitches, but they put good swings on them because I was behind in the count the entire night. The best thing is learn from it, go forward from it."

Mark Leiter Jr., a 26-year-old rookie whose father pitched in the majors, relieved Pivetta and saved the Phillies' bullpen with 4 1/3 scoreless innings, allowing two hits with no walks and nine strikeouts (eight swinging).

Leiter's nine strikeouts are tied for the fifth-most by a reliever in Phillies history and the most since Lowell Palmer struck out 10 against San Francisco on May 3, 1970.

Leiter became the sixth reliever in major league history to record nine strikeouts without allowing a run or walk. The last was Bruce Ruffin, who began his career with the Phillies, on Sept. 14, 1993, when he was pitching for the Rockies against Houston.

"He threw all his pitches for strikes," Phillies manager Pete Mackanin said of Leiter. "Threw strikes with all his secondary pitches and he's got quite a few of them. He made a lot of good hitters look bad tonight. Can't say enough about his performance. He's a rookie. He's getting his feet wet. But he pitched like a 10-year veteran tonight. He put on a clinic for every pitcher in baseball. It was really a lot of fun to watch."

Gray allowed his only run in the fourth. He gave up an infield single to Freddy Galvis to start the inning, followed by Daniel Nava's single that sent Galvis to third. He scored when Nick Williams grounded into a double play.

After Gray departed, left-hander Zac Rosscup, who was recalled Sunday, began his second stint with the Rockies this season. He gave up two singles to start the eighth followed by a three-run homer by Nava, who finished a double shy of the cycle. Galvis singled home the final Phillies run in the ninth.

NOTES: Rockies LHP Kyle Freeland (left groin strain) was placed on the 10-day disabled list after coming out of his start Friday night in the first inning. ... Rockies RHP Scott Oberg was optioned to Triple-A Albuquerque, and RHP Carlos Estevez and RHP Shane Carle were recalled from that club. ... Rockies RHP Chad Bettis (testicular cancer) was reinstated from the 60-day disabled list and optioned to Albuquerque. ... Phillies RF Aaron Altherr (right hamstring strain) was placed on the 10-day disabled list, and OF Cameron Perkins was recalled from Triple-A Lehigh Valley.