With the win, the D-backs avoided a sweep in the three-game series.
Corbin (6-7) pitched eight innings for the first time and allowed a pair of runs on eight hits while striking five. But it was his hitting that had the clubhouse buzzing, particularly his headfirst slide into third on the triple.
"Corbin is an athlete, man," said D-backs outfielder Justin Upton, who added three RBIs of his own. "He helped himself out."
After Paul Goldschmidt reached on an error to start the fourth, Giants starter Ryan Vogelsong (12-9) struck out Ryan Wheeler before Cody Ransom doubled. That's when the Giants decided to walk Parra to load the bases for Corbin.
"My first at-bat, he threw two heaters in and I just stood there," Corbin said. "Didn't even take the bat off my shoulder. So he got to two strikes again and that's just what I was sitting on, just put the bat on the ball."
What about that headfirst slide?
"You're kind of just feeling it; you kind of just go with what you're doing," he said. "It's just instincts. They just kind of took over. In Little League and stuff, that's what I did a lot. I haven't had the opportunity to do it here."
Corbin legged out a standup triple during Spring Training, and his dive did not raise any eyebrows among his teammates who have seen a video of exploits on a different playing surface.
"He can dunk a basketball," Goldschmidt said. "I didn't even think about [the headfirst slide] until I heard some other guys talking. When you're in the moment, you're not thinking about that."
The last time Corbin faced the Giants, he allowed four runs in the first inning before shutting them down after that.
On Sunday, he started off shaky, allowing a leadoff double to Angel Pagan, who would come around to score on Buster Posey's single.
"They're going to come out swinging," Corbin said. "They put a run up in the first and I think the last time I faced them they did the same thing, and then just kind of mixed it up after that and kept them off balance."
Corbin played on the Giants' aggressiveness to keep his pitch count down, and that allowed him to get through the eighth inning, which had been a problem for him in his first 13 big league starts.
Getting him over that hump was a big reason D-backs manager Kirk Gibson stuck with him even when the first two batters of the eighth reached. Corbin was able to settle down and strike out Pablo Sandoval and Posey before Hunter Pence flied out to end the inning.
"As you guys remember, he's had games where he has had low pitch counts and then as soon as he hit the seventh inning he was done," Gibson said. "It's good to see him get additional innings and make a step forward."
Upton, who homered Saturday, had a two-run double off the center-field wall in the third and hit a solo homer in the sixth.
"He's on a bit of a roll," Gibson said. "He's getting the head out and driving balls. I like to see that; it's obviously important to us."
Said Upton, "Just trying to get some good pitches to hit, be a little more patient, see the ball over the middle of the plate and put a good swing on it. I've tried to stay positive all year and keep going. Stringing together a couple of good days is nice."