Voted to the All-Star Game for the second time and a candidate to start in next week's Midsummer Classic, Cueto (13-1) allowed one run on seven hits with eight strikeouts and one walk while going the distance for the fourth time this season. The performance gave San Francisco's slumping bullpen a much-need break.
Cueto also became the first Giants pitcher since John Burkett in 1993 to win 13 games before the All-Star break.
The Giants have won five of seven. Buster Posey homered for the second time in three days, Brandon Belt doubled and tripled and Brandon Crawford drove in two runs for San Francisco.
Posey struck out looking with a runner on third in the first inning before hitting his 11th home run of the season off Rockies starter Jorge De La Rosa (5-7) in the sixth.
De La Rosa allowed three runs over seven innings with five strikeouts and one walk. The Colorado lefty has lost two straight since his four-game winning streak.
Grant Green walked and scored on Belt's RBI triple in the first. Belt scored on Crawford's two-out single.
Green also scored on a wild pitch in the eighth and Crawford added a sacrifice fly to make it 5-1.
Rookie sensation Trevor Story drove in Colorado's lone run in the fourth on a fielder's choice grounder with the bases loaded.
CUETO AT THE PLATE
San Francisco's starter wasn't as dominant at the plate as he was on the mound but still managed to end an 0-for-26 slump when he singled off De La Rosa in the second inning.
Giants: Manager Bruce Bochy said he hopes to know by this weekend when OFHunter Pence (right hamstring surgery) will begin a rehab assignment. Pence has been taking batting practice and running. "He's coming along great, right on pace," Bochy said. ... RHP Matt Cain (strained right hamstring) is scheduled to throw 65 pitches in a rehab start with Triple-A Sacramento on Friday. ... 3BMatt Duffy (strained right Achilles tendon) has been running on a treadmill. ... RHP Cory Gearrin was placed on the 15-day disabled list with a strained right shoulder. ... RHP Albert Suarez was called up from Sacramento to take Gearrin's place on the roster.
Rockies: Right-hander Chad Bettis (6-6) pitches Thursday in the opener of a four-game home series with Philadelphia. Bettis has a 6.58 ERA over his previous five starts.