SAN FRANCISCO -- San Francisco Giants ace left-hander Madison Bumgarner insisted he and his teammates were embarrassed by the shellacking put on them by the Colorado Rockies in Thursday's series opener.

Fortunately for the Giants, they had just the guy available Friday night to do something about it.

Bumgarner himself.

The former World Series Most Valuable Player recorded double-digit strikeouts for the first time this season, fanning 10 Rockies in pitching the Giants to a 6-4 victory.

Brandon Crawford smacked a three-run home run, his fourth of the season, as the Giants celebrated former great Willie Mays' 85th birthday by avenging their 17-7 drubbing of the night before.

"We had to come in and win today," Bumgarner claimed. "Embarrassing days like yesterday, we've had a few. This team takes it personal. Nobody's going to come in pouting and get their feelings hurt."

Bumgarner (4-2) overcame a four-run second to pitch 7 1/3 innings en route to his third consecutive win.

The left-hander shut out the Rockies on four hits after the second inning before handing the ball to right-hander Cory Gearrin with one on and one out in the eighth.

"That's kinda who I am, who I want to be. I'm never going to give in," assured Bumgarner, whose double-digit strikeout game was the 26th of his career. "It might not be good enough sometimes, but you're always going to get what I got."

Bumgarner allowed a total of seven hits and four runs, three earned, in his 7 1/3 innings. He issued just one walk.

"That's probably his best game," Giants manager Bruce Bochy observed. "After the tough second, he toughened up. He went out there and got it done for us."

Guerrin gave up a one-out single to Rockies slugger Nolan Arenado in the eighth, but then struck out Mark Reynolds and got Ryan Raburn to ground out with the potential tying run on base.

Closer Santiago Casilla pitched a 1-2-3 ninth with two strikeouts for his seventh save.

"It's a tough group," Bochy said of his club. "You're going to have to deal with ugly games. It's all about being resilient. We found a way to get it done."

Right-hander Chad Bettis (3-2) couldn't hold an early 4-0 lead and suffered the loss for the Rockies. He allowed eight hits and five runs in six innings, walking two and striking out four.

"The three-run homer Crawford got was a big shot," Rockies manager Walt Weiss lamented of the sixth homer, all on the road, allowed by Bettis this season. "It put them right back in the game."

Hunter Pence, returning from a sore back that sidelined him for Thursday's series opener, had three of the Giants' nine hits, all singles.

Matt Duffy had two hits, including an RBI triple, and Brandon Belt added a run-scoring double for the Giants, who snapped a two-game losing streak.

Reynolds had three hits, all singles, for the Rockies, who fell to 5-3 on their current 10-game trip. The veteran is hitting .533 (8-for-15) against the Giants this season.

Arenado added a single and a double in Colorado's eight-hit attack, lengthening his hitting streak at AT&T Park to 10 games.

After falling behind by four runs early, the Giants rallied for a 5-4 lead in the fifth on Duffy's tying triple and Pence's tie-breaking single. Denard Span set up the two-run inning with a leadoff bunt single.

The Giants' rally began with Crawford's homer in the bottom of the second. It followed a walk to Belt and Pence's first hit, a single.

"That was huge for us," Bumgarner gushed. "We had a rough (top of the) second inning all the way around. To come back in and get right back in the game ... that was huge."

San Francisco was forced to fight an uphill battle after its defense for the second night in a row let it down and helped Colorado build a big inning.

This time, it happened in the top of the second after Arenado had doubled and came home on Reynolds' single to open the scoring.

Consecutive off-line throws by Duffy at third (Raburn was credited a hit) and second baseman Joe Panik allowed a second run to score.

Dustin Garneau followed with a sacrifice fly and Bettis a safety squeeze that plated Gerardo Parra, completing the four-run uprising that produced a 4-0 lead.

"Scoring 17 runs here doesn't happen very often," Rockies second baseman DJ LeMahieu noted. "We knew we were going to have to grind out the rest of the series, especially against Bumgarner. I wish we could have saved some of those runs."

NOTES: Popular ex-San Francisco 49ers coach Jim Harbaugh and President Obama gave video tributes to Willie Mays, who celebrated his 85th birthday in a luxury box. ... Rockies CF Gerardo Parra also had a birthday Friday. Awkwardly, he stood in center field (Mays' old stomping grounds) while the crowd sang "Happy Birthday" to the Hall of Famer in the bottom of the third inning. ... The come-from-behind win was the third of the season for the Giants in a game they once trailed by four or more runs. ... The winning team has averaged 10.2 runs in the five games between the Rockies and Giants this season. ... Before the game, the Giants designated RHP Vin Mazzaro for assignment. Mazzaro retired only one of the 10 batters he faced in the Rockies' 13-run fifth inning Thursday, watching a 0.00 ERA become 63.00 in the process. ... The Giants promoted RHP Albert Suarez from Triple-A Sacramento to fill the roster spot.