DENVER -- A barrage of singles and some very timely hitting Saturday helped the Colorado Rockies continue their dominance over the San Francisco Giants with a 5-1 victory.

Colorado scored all its runs with two outs in support of rookie Kyle Freeland (8-4), who pitched six innings before three relievers finished up. Freeland took a Joe Panik line drive off his left forearm in the third, but by then had settled in a groove after throwing 48 of his 94 pitches in the first two innings.

The Rockies have won nine of 10 games against the Giants this season, including eight in a row. That is Colorado's longest winning streak in franchise history against any National League West opponent.

The win was the fourth straight for the Rockies (45-26), their 11th in 14 contests and moved them a season-high 19 games above .500. The victory assured the Rockies of winning this four-game series, giving them a 16-4-3 record in series this season.

The Giants (26-44) have lost five straight and 14 of their past 18 contests to fall a season-high 18 games below .500. They trail the first-place Rockies by 18 1/2 games, the first time the Giants have been that far from first place prior to the All-Star break since 1985.

Giants manager Bruce Bochy was direct when asked if there was a common thread in this series against the Rockies.

"Yeah we're losing every game, that's the common thread. We're not doing enough to win the ballgames," Bochy said. "We score 17 runs in the first two games, and we can't get a win. And we get a pretty good pitching job, and we get one run today. That's kind of how it's gone for us."

Giants starter Matt Cain (3-6) gave up nine singles and two runs (one earned) in five innings. He stranded nine runners.

Freeland got 11 outs on ground balls while recording his team-leading 10th quality start. He managed just three strikeouts, but they were crucial.

Freeland walked Kelby Tomlinson to open the game but picked him off. Panik and Hunter Pence followed with singles, but Freeland struck out Buster Posey and Austin Slater.

With runners on first and second in the sixth, Freeland struck out pinch hitter Brandon Belt to end the inning and his outing. Freeland fell behind Belt 2-0 but deferred to catcher Tony Wolters and struck Belt out on a high 3-2 fastball clocked at 92.3 mph.

"I shook Tony to go to a slider," Freeland said. "Then he kind of looked at me and shook his head. I stepped off and said, 'Let's do it,' and we attacked him with the heater."

The left-handed hitting Belt represented a power threat but one with severe limitations as of late. He is 0-for-18 with just two hits in his past 29 at-bats and does not have a hit in his past 23 at-bats against left-handed pitchers.

No. 8 hitter Wolters, who went 2-for-4 with two RBIs, singled home the Rockies' first run in the second inning and another in the seventh and is batting .301 with a .400 on-base percentage. Pinch hitter Pat Valaika followed Wolters in the seventh with a run-scoring double -- Colorado's only extra-base hit after 13 singles. Every player in the starting lineup, including Freeland, had at least one hit.

Trevor Story put the Rockies ahead 2-1 when he grounded a single up the middle with two outs in the fifth, scoring Ian Desmond. Carlos Gonzalez walked, and Desmond took third on a passed ball before Story drove in his fifth run in six games.

Nolan Arenado's two-out single in the sixth boosted the Rockies' lead to 3-1. The hit scored Raimel Tapia, who singled with one out and moved to second on a groundout. Tapia has recorded four straight multi-hit games and five consecutive multi-hit starts.

Three straight two-out singles in the second, the last by Wolters, gave the Rockies a 1-0 lead. Gorkys Hernandez tied the game at 1 with a two-out single in the fourth. The hit scored Nick Hundley, who doubled into the right-field corner with one out.

The Giants went 1-for-7 with runners in scoring position and stranded 10 runners. Cain made his 39th career start against the Rockies, the most by any pitcher in major league history. For the ninth time in 14 starts, Cain received one or fewer runs of support, all part of the Giants' pervasive gloom.

"It's not really one thing you can put your finger on," Cain said. "It's something we've got to find a way to keep grinding though. It's definitely been hard for all the guys, the staff. It's not been easy."

NOTES: Rockies 3B Nolan Arenado was charged with his first error of the season when he was unable to come up with C Nick Hundley's grounder in the second. ... Rockies RHP Chad Bettis (cancer) is scheduled to throw 15 fastballs Sunday in a bullpen session, his first at 60 feet, 6 inches with the catcher positioned behind home plate. ... Giants LHP Madison Bumgarner (bruised ribs, left shoulder sprain) threw about 40 pitches in a simulated game at the team's complex in Scottsdale, Ariz. ... Giants 1B Buster Posey (left ankle) was cleared to catch and will do so Sunday but started at first base. ... Giants SS Brandon Crawford and CF Denard Span, who pinch hit in the ninth, were given a day of rest, and 2B Joe Panik might rest Sunday. ... Giants INF Eduardo Nunez (left hamstring) is available in an emergency but likely won't return to the lineup before Monday at Atlanta. ... Rockies CF Charlie Blackmon did not start for just the second time this season.