The slow beginning occurred one night after the Giants had taken a 6-3 victory in the opener of the four-game series and seemingly halted the Rockies' momentum. After going 4-2 on a road trip to Florida and Washington, D.C., the Rockies were tired and sloppy.
But Colorado showed Saturday that it takes more than one game to stop a turnaround that started in late May.
"The team that I've been managing since the 29th of May showed up in about the fifth inning," Rockies manager Jim Tracy said.
But after Troy Tulowitzki and Brad Hawpe singled off San Francisco starter Joe Martinez to open the sixth, Stewart blasted a Martinez pitch the opposite way into the left-field stands.
Stewart was in an 0-for-16 skid before his second-inning single. He has shown the ability to hit with power to all fields, yet he's hitting just .227 this season. Stewart plays regularly, though, because he is capable of powerful outbursts, like when he had 12 hits and four homers en route to being named National League Player of the Week on June 7.
"That's how it started, right there," Tracy said. "He realized, 'If I hit the ball to the big part of the field and work my way around, and keep that thought process' -- that's what got him going."
Stewart, who finished with four RBIs, crossed the plate with his usual skyward gesture, but with elation and relief. Teammates felt every bit as uplifted.
"We know that everybody can do great things," said Carlos Gonzalez, who went 1-for-3 with two runs scored from the leadoff position. "Stewart is a guy who had stopped hitting home runs for a while. But he's still got the power. He's still got the talent."
By the time the inning was done, pinch-hitter Seth Smith and Dexter Fowler each had tripled in a run and Todd Helton had launched his 12th homer of the season, a solo shot off losing pitcher Justin Miller (2-2). The Rockies had seven hits in the inning.
"Big at-bats with men in scoring position, situational hitting with guys at third -- all of that began to reappear," Tracy said. "That's something you have to sit and be very patient with when it goes away for a little bit of a period of time, then it will show back up."
Giants manager Bruce Bochy knows that games like Saturday's crop up often in Colorado.
"This is a Coors Field game," Bochy said. "I've seen it many times. Both sides were swinging the bat. It was one of those wild games."
The big sixth made a winner of Jorge De La Rosa (12-8), who needed the help. De La Rosa improved to 12-2 in his past 14 starts. But he yielded two-run homers to Nate Schierholtz in the second and Ryan Garko in the third, giving up six runs on eight hits -- though he struck out five -- in six innings.
Remember the De La Rosa who would fall apart once momentum went against him? Well, he made that pitcher a faint memory on Saturday night. As the final score indicated, runs would be plenty, but he settled down after each homer. After the Rockies' two-run fourth, De La Rosa threw two scoreless frames that proved important.
"I really hope he realized what he did tonight, because if he does, that's the hurdle I've been talking about time and time again for him to go over and become a winning-type pitcher," Tracy said.
De La Rosa began the year 0-6 in his first nine starts, but the Rockies scored more than four runs for him just twice and fewer than four five times in that span. Of course, when a comeback like Saturday's takes place, a pitcher can trust that his offense will be there for him when he really needs it.
"We have very good hitters," De La Rosa said. "I try to keep the game close every time I go out there and wait for my teammates."
The Rockies added four runs in a seventh inning that saw Giants relievers Bob Howry and Merkin Valdez issue bases-loaded walks.
Garko added a second homer off Matt Daley for two runs in the eighth, and Aaron Rowand followed with a solo shot.
After the Giants' Pablo Sandoval hit a two-run homer with one out in the ninth off Matt Herges to make it a three-run game, Huston Street entered and converted his 33rd save in 34 chances this season.
After missing Friday night's 6-3 loss to the Giants with a stomach bug, Rockies shortstop Troy Tulowitzki returned to the lineup and went 2-for-3 with an RBI.