PHOENIX -- Two years ago, Giants outfielder Alex Dickerson arrived on the scene and became one of the first underrated pickups of the Farhan Zaidi regime.

Acquired from the Padres in exchange for Minor League pitcher Franklin Van Gurp, Dickerson earned his first callup with the Giants on June 21, 2019, and promptly delivered one of the best debuts in franchise history. Dickerson crushed a grand slam and went 3-for-5 with a career-high six RBIs to propel San Francisco to a blowout win at Chase Field.

The lefty slugger quickly endeared himself to his Giants teammates, who began celebrating his exploits at the plate by emphatically chanting an abbreviated version of his surname in the dugout.

As he showed from the beginning, Dickerson is capable of carrying the Giants lineup when he’s hot, but he’s struggled to get going offensively this season. Still, Dickerson recaptured some of the early magic with another breakout performance in the desert, belting his third career grand slam to help the Giants survive a late surge by the D-backs and escape with an 11-8 win in 10 innings on Monday night.

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“He’s had quite a bit of success against the D-backs,” Giants manager Gabe Kapler said. “He’s had quite a bit of success in this ballpark. I think he feels especially confident.”

Dickerson’s slam capped a five-run rally that extended the Giants’ lead to 7-1 in the fifth inning, but the D-backs stormed back after Josh Reddick and Asdrúbal Cabrera each drilled two-run shots off right-hander Anthony DeSclafani to cut the deficit to two in the bottom half of the inning.

Wilmer Flores, who entered the game as part of a double-switch in the fifth, made it 8-5 with his 14th homer of the year, but Arizona tied the game by scoring three runs off reliever Jay Jackson in the seventh. A two-out single by Carson Kelly put the winning run aboard for the D-backs in the bottom of the ninth, but lefty reliever Jarlín García barehanded a feed from Flores to record the final out at first base and force extra innings.

Buster Posey sparked the decisive rally in the 10th by ripping a leadoff double to left field to knock in Brandon Crawford, the automatic runner, and put the Giants ahead, 9-8. San Francisco added a pair of insurance runs on an RBI single by Steven Duggar and a safety squeeze bunt by Donovan Solano to hand a three-run lead to García, who worked another scoreless inning to end the four-hour affair and pick up his third win of the year.

The Giants improved to 10-1 against the last-place D-backs this season, extending their lead in the National League West to 3 1/2 games over the idle Dodgers.

“The D-backs, give them credit, they never quit that entire game and came all the way back,” Dickerson said. “We had to battle. Everybody in our clubhouse has confidence that we have a winning mentality and we’re not going to panic. We’re just going to get out there and try to get the job done.”

Dickerson, 31, entered Monday batting .217 with a .687 OPS over 80 games this year, but he said he felt good coming into the Giants’ series opener at Chase Field. He went hitless in his first two at-bats of the game, but he felt something click when he was on the on-deck circle later in the night.

“It’s tough to describe,” Dickerson said. “It was a feeling of how my legs were set up and something I really hadn’t felt all year. … All of a sudden, it was a reminder like, ‘Oh, that’s how they’re supposed to work.’”

Dickerson then stepped up to the plate with the bases loaded and one out in the fifth and snapped an 0-for-17 skid by hammering a 1-1 slider from Arizona reliever J.B. Bukauskas 437 feet out to right field for his career-high 11th home run of the year. He was all smiles when he returned to the Giants’ dugout, earning plenty of high fives from his teammates and a hug from Mike Yastrzemski, who put San Francisco on the board with a two-run shot in the third.

“They were extremely happy,” Dickerson said. “It hasn’t been the greatest year for me to this point, but they know and I know that I’m better than how I’ve played. I just needed that kind of day where it all comes together. It was a good feeling to have everybody pulling for me.”

Dickerson added a 415-foot triple off the center-field wall in the seventh to finish 2-for-5 with four RBIs. His incipient turnaround is well-timed, as the Giants are expecting to get three veteran infielders -- Tommy La Stella, Brandon Belt and Evan Longoria -- off the injured list soon, which will likely lead to a few painful roster decisions.

The success of LaMonte Wade Jr. and Darin Ruf, plus the arrival of Kris Bryant, have already cut into Dickerson’s playing time in left field, but if he can continue to build off the momentum he built on Monday, he should have the opportunity to re-establish himself as a key piece for the Giants.

“I don’t even think he needs to be hot,” Kapler said. “I just think he needs to be the better version of Alex Dickerson. That’s a guy who’s a really tough out at the plate against righties and occasionally has games with big damage like he had today. I don’t want Alex to put any additional pressure on himself to be perfect every time out. Just be productive and keep the line moving.”