SAN FRANCISCO -- The D-backs appeared to be dead in the water on two different occasions. The Giants led by five runs in the sixth inning, then by two in the ninth. The odds were seldom in Arizona’s favor. At times, a loss felt less like a question and more of an inevitability.

Evidently, no one told that to Arizona, which erased two separate deficits with two resounding comebacks, shocking the orange-and-black faithful in the process. And although the D-backs lost 8-7 to the Giants on Tuesday at Oracle Park by way of the walk-off, the D-backs had fought back, refusing to lay down for MLB's best team.

“I’m extremely pleased with that,” said manager Torey Lovullo. “Our offense had an uphill battle there. … We did a really nice job of executing a plan and putting some runs on the board, and we closed the gap real quickly.”

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Arizona’s first rally started with, of all people, starting pitcher Zac Gallen. When the right-hander, who allowed four runs in the first inning before settling down, stepped into the box after Josh Rojas flied out, San Francisco’s win probability sat at a very comfortable 97 percent, but Gallen was about to shift those odds.

Gallen roped a one-out double with an exit velocity of 103 mph into the left-field gap for the first extra-base hit of his career. With the benefit of retrospect, that double wasn’t just a novelty; it was the spark plug.

“Torey knew I was frustrated with how the first inning went,” Gallen said after allowing five runs across six innings. “He was like, ‘Hey, I’ll give you the green light. Get a strike, try and get something out over and take your aggression out on that swing.’”

Maybe the unexpected nature of Gallen’s two-bagger, his first extra-base hit since high school, had awakened something within Arizona’s hitters, because from there, the avalanche began.

Nick Ahmed followed Gallen’s double with a double to drive in his starting pitcher. 5-1. Ketel Marte joined in on the fun, doubling home Ahmed. 5-2. After Kole Calhoun grounded out, Carson Kelly kept the extra-base-hit party going with a triple, the first of his career. 5-3. Then, Asdrúbal Cabrera completed the comeback effort, turning on a hanging slider and sending it over the center-field fence. Just like that, this game was tied.

It happened so fast, so quickly, partially because of Wood’s frenetic pace on the mound. Arizona’s rally completely sucked the air out of a home crowd that was expecting to cruise to a win before being serenaded by Tony Bennett’s “I Left My Heart in San Francisco.” By the end of the half-inning, the contest had turned into a barnburner.

That was one comeback. Then, Arizona had to do it again.

San Francisco reclaimed the lead in the bottom of the eighth. Brandon Crawford smacked an opposite-field double to drive in Buster Posey all the way from first, then scored on Sean Poppen’s errant pickoff attempt to first base. With only three outs remaining, coming back from this deficit would be even more challenging.

Down a pair in the ninth against closer Jake McGee, the D-backs loaded the bases with no outs thanks to back-to-back singles from Cabrera and Pavin Smith and a walk by Christian Walker. Josh Rojas struck out for the inning’s first out, but Josh VanMeter came off the bench to draw a bases-loaded walk, pulling the deficit to one. Then, Nick Ahmed made up for an aggressive baserunning out in the eighth inning with the game-tying sacrifice fly. Another deficit, another comeback.

Ultimately, a win wasn’t in the cards as Walker couldn’t corral a sharp single off the bat of Bryant, allowing LaMonte Wade Jr. to score and hand the D-backs the loss.

The ending stung, yes, but to get to that position the D-backs pushed an elite team to the brink instead of fading into the night, a moment of growth for a team trying to learn how to win.

“We haven’t shut down,” Lovullo said. “We fight. We play hard. We just have to find a way to make the plays and make the pitches and have the at-bats to win a baseball game. And we will. I’ve been saying it for the past couple days. To get to where we want to get to, we’ve got to learn how to win these baseball games.”