SAN FRANCISCO -- Kevin Gausman was hoping he wouldn’t be moved at last week’s Trade Deadline, but he figured it would be best to be prepared. He packed up all his stuff to expedite a potential departure, but one never came. 

With the Giants in the midst of another summer surge, president of baseball operations Farhan Zaidi opted to hold on to trade chips like Gausman, Johnny Cueto and Tony Watson to give the club a chance to continue its push for the playoffs. One week later, the Giants appear intent on validating that faith. 

After defeating the D-backs, 4-2, to clinch a series victory on Monday night at Oracle Park, the Giants (21-21) climbed back to .500 for the first time since they were 5-5 on Aug. 2.

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San Francisco became the first club to score more than three runs against budding right-hander Zac Gallen, stringing together a four-run rally in the sixth inning to back a strong outing from Gausman, who earned his 50th career win after striking out nine over six innings of one-run ball.

It was hard to envision that Gausman would still be around in September when the Giants fell to 8-16 on Aug. 17, but they resuscitated their season with a 13-5 run that has catapulted them back into the National League Wild Card mix. They are currently in playoff position with 18 games left to play and appear to be hitting their stride as they enter the final third of the regular season. 

Gausman is grateful to still be around for the ride, even if it meant having to unpack all his bags. 

“That was the unfortunate thing,” Gausman said. “I had to kind of unpack my stuff, but that's OK. I was definitely happy to be back here. ... More than anything, I just feel confident in our team.” 

Monday’s victory once again showcased the resilience and depth of the Giants’ offense, which has emerged as the club’s biggest strength this year. Gausman and Gallen, who both benefited from the late-afternoon shadows at Oracle Park, were locked in a pitchers' duel until the Giants finally broke through with a series of quality at-bats in the sixth.  

Pablo Sandoval, who earned his first start of the season at third base after Evan Longoria was scratched with right glute soreness, drew a leadoff walk off Gallen to jumpstart the decisive rally. After Joey Bart singled and Mauricio Dubón walked to load the bases, Mike Yastrzemski pulled a single through the right side to tie the game, 1-1.

“It started with Pablo with a great walk,” Yastrzemski said. “Joey had a great AB. Dubi had one right after him. Those guys have been working really hard this year, and it's great to see it pay off. When you see the day in and day out work that guys go through, it's almost more rewarding to watch somebody else do it and see their perseverance pay off. I’m just really happy for those guys. They were the ones that got everything going, so all the credit goes to them.” 

Darin Ruf, another sub who entered the game in the fourth after Alex Dickerson exited with a right knee injury, followed by lining a first-pitch cutter to center field for a two-run, go-ahead single. Donovan Solano then singled to re-load the bases for the Giants and chase Gallen, who departed without retiring any of the six batters he faced in the sixth.

Arizona reliever Junior Guerra replaced Gallen and walked Brandon Belt to force in another run and extend San Francisco’s lead to 4-1. Gallen was charged with four runs over five-plus innings, snapping his streak of 23 consecutive starts with three or fewer earned runs to start his career, a Major League record.

"It just seems like every night there's a couple of guys who have really good quality at-bats in big situations,” Gausman said. “It just seems like every night, it’s somebody different. When you don't have to rely on your top four hitters to win the game every night, I think it makes it really hard on the opposing team. The guys have done such a good job of battling through at-bats and making the pitcher kind of have to make a mistake eventually."

The Giants will have a chance to secure their first winning record since they were 5-4 on Aug. 1 when they kick off a two-game series against the Mariners on Tuesday night. They’ll head into the matchup with burgeoning confidence and a resolute belief that they have the talent to sustain their push for the playoffs over the final few weeks of the season.

"It's gratifying,” manager Gabe Kapler said. “It certainly speaks to the fight that this club has. We can go back a couple of weeks and find some pretty heartbreaking losses. These guys are resilient. They bounce back from those losses, they bounce back from in-game deficits. I think the character of this team is continuing to shine through."