DENVER -- On the 4,802nd plate appearance of his career, Carlos Gonzalez did something for the first time -- something rather unexpected and extremely gratifying.

With two outs in the ninth and the bases loaded, Gonzalez drew his first walk-off walk.

It came on four pitches and lifted the Colorado Rockies to a 4-3 win over the San Francisco Giants.

When Cory Gearrin missed badly with his fourth pitch, Gonzalez raised his hands triumphantly and headed to first base.

"At that point, it's not about getting a hit, it's not about hitting a home run," Gonzalez said. "It's about getting the job done. I was happy I didn't need to swing the bat to win the game."

The victory increased the Rockies' lead to 1 1/2 games over Milwaukee for the second National League wild-card spot. The Brewers endured a walk-off, 5-4 loss at Cincinnati when Billy Hamilton homered in the ninth.

The Rockies broke a four-game losing streak and won for just the fifth time in 15 games. They are 8-0 against the Giants this season at Coors Field, where they have beaten San Francisco nine consecutive times.

Charlie Blackmon led off the ninth with a double off Steven Okert (1-1). Left fielder Mac Williamson made an unsuccessful sliding attempt to catch the ball, which glanced off his glove.

"Okert gets the fly ball, and we don't handle it," Giants manager Bruce Bochy said. "That puts us in a tough position. The ball was up there a long time. He got the glove to the ball, he just dropped it."

After Nolan Arenado was intentionally walked with one out, Okert walked Gerardo Parra on four pitches. Gearrin came on to face pinch hitter Pat Valaika and struck him out on three pitches before walking Gonzalez.

"He tried to throw a slider 1-0, and he got in the hole with 2-0," Gonzalez said. "I was in control, I was relaxed the whole at-bat, and I'm really happy I got the job done."

Gearrin's poor location enabled the Rockies to win via a walk-off walk for the second time this season and the sixth time in franchise history.

"I pulled that changeup on the second pitch, a great opportunity for us because he's an aggressive hitter," Gearrin said. "But I just didn't execute the pitch. It's just unacceptable for me to come in and not throw strikes and make that a competitive at-bat."

Greg Holland (3-5) pitched the ninth as the Rockies used four relievers to blank the Giants for 4 2/3 innings after starter Chad Bettis gave up three runs and five hits in 5 1/3 innings.

The Giants took a 2-0 lead against Bettis on home runs by Joe Panik (first inning) and Denard Span (third inning). Panik and Span had three hits apiece and combined to score all of San Francisco's runs.

Blackmon hit his 33rd homer in the bottom of the third, a solo shot, and Bettis hit a game-tying single in the fourth.

The RBI was the first for Bettis in six at-bats this year and just his fourth in 98 career at-bats.

"I was just trying to shoot the ball the other way and just happened to hit it," said Bettis, who then scored on DJ LeMahieu's single to put the Rockies ahead, giving them a lead for the first time in 39 innings.

That was the final inning for Giants starter Chris Stratton, who needed 98 pitches to work four innings. He gave up eight hits and three runs with three walks and four strikeouts.

Bettis didn't face a batter with a runner in scoring position until Span led off the sixth with a double to left field. Panik followed with a run-scoring single up the middle to tie the game at 3 before the Giants lost for the fourth time in five games and the ninth time in their past 11.

Other than Span and Panik, the Giants got a first-inning single from No. 3 hitter Buster Posey, but the fourth through ninth hitters went a combined 0-for-21.

"We didn't get a hit on the back end of the batting order," Bochy said. "That went dry on us. It made it tough because we got a lot of production from the first two guys."

NOTES: Giants 3B Pablo Sandoval went 0-for-4, extending his string of consecutive hitless at-bats to 33, the longest in the majors this season ... Rockies RHP Tyler Chatwood will make his first start Tuesday since Aug. 2 and his third start since the All-Star break. ... Rockies SS Ian Desmond made his first start at the position since Oct. 4, 2015, while playing for Washington but moved to first base in the sixth. ... RHP Matt Cain is away due to a family matter and unlikely to rejoin the Giants until they begin a homestand next Monday. ... Rockies CF Charlie Blackmon became the 10th player in team history with 60 multi-hit games in a season and the first since Todd Helton in 2003. ... Rockies 2B DJ LeMahieu extended his season-high hitting streak to 12 games.