PHOENIX — Maybe this isn’t the same Madison Bumgarner in his eighth game back from a shoulder injury suffered in a dirt bike accident. It’s certainly not the same championship-caliber San Francisco Giants team.

In the thick of the Wild Card race, the Arizona Diamondbacks will take the second win in a row over the 52-79 Giants for their fifth win in their past six games overall.

The D-backs rode Taijuan Walker’s strong start and the bullpen’s continuation of shutdown pitching in a 2-1 victory where the only offense came by way of two home runs off Bumgarner. But the storyline was Walker (7-7), who pitched 6.1 innings, allowing four hits — including a home run — and a walk to go with three strikeouts.

It was the starter’s first win since June 21 and first at Chase Field since April 27.

“He’s been very unfortunate. He’s had some bad luck, maybe a pitch or two hasn’t gone his way where it’s created a little bit of a backwards reaction. And he keeps just fighting on,” D-backs manager Torey Lovullo said.

“His first fastball of the game, he wasn’t trying to feel his way into the zone. That seemed to pace his day, because he was sitting in the mid-90s pretty much all day long,” the manager added. “Once in a while he works his way into his outing with his velocity, but not today.”

Walker had an early lead to work with. Facing a 1-2 count in the bottom of the first inning, D-backs center fielder A.J. Pollock lined a low sinker off Bumgarner to left-center field for a solo home run.

“You’re just trying to get something you can handle out over the plate,” Pollock said. “Get two strikes on me and then he tried to sneak one by me — was able to get barrel on it and glad it got out of the park.”

But after three perfect frames by Walker, the Giants’ Jarrett Parker jumped on the right-hander’s first mistake, taking a high fastball for a home run to the deep part of center field to tie the game, 1-1, in the top of the fourth.

It wasn’t long before Arizona responded. Placing the ball just left of where Pollock’s home run dropped, Arizona outfielder J.D. Martinez caught a fastball in the middle of the zone for a solo home run in the bottom of the fourth to put Arizona ahead by a run once again.

That was the last mistake by Bumgarner, who went seven complete frames and allowed five hits and a walk to go with seven strikeouts.

The two home runs aside, the Diamondbacks put only three players on base with hits and one more with a walk. The last of those hits, a Brandon Drury lead-off double in the bottom of the seventh, saw Adam Rosales, Daniel Descalso and Gregor Blanco fail to advance the runner past second.

The D-backs were able to breathe easier about the missed opportunity because they still led after holding off San Francisco threats in the fifth and sixth.

Testing Walker’s mettle following the Parker homer, Brandon Crawford led off the fifth with a single before Joe Panik hit a one-out single to put runners on the corners. But Walker responded by striking out Ryder Jones and Bumgarner swinging to get out of the frame. A two-out triple by Parker in the top of the sixth again put the pressure on Walker, but he got catcher Buster Posey out on a foul-tip into catcher Chris Iannetta’s glove.

“My pitch-count’s been getting really high and, you know, when I got ahead I tried to put them away and got some weak contact,” said Walker, who threw 108 pitches and induced eight groundouts while striking out just three.

Relievers Andrew Chafin (0.2 innings), David Hernandez (1.0 inning) and Fernando Rodney (1.0 inning) combined to allow a hit and no walks with four strikeouts to follow Walker.

“Bullpen came on board and shut the door,” Lovullo said. “I think those close ballgames, those 2-1 ballgames are an indication of how the team is feeling about yourselves.”

THE GOOD 

–A.J. Pollock tracked a streaking liner by Brandon Crawford into shallow right-center field and made the catch at his feet while still standing to avoid a lead-off hit in the top of the seventh. After Walker walked Pablo Sandoval and was pulled from the game, Chafin allowed a hit to put runners on first and second before inducing a pop-out and striking out Bumgarner looking, to the Giants pitcher’s (appropriate) dismay.

–David Hernandez pitched the full eighth, earning two outs via pop-out and the third, against the previously-hot Parker, via a strikeout.

–Fernando Rodney closed with a groundout and two strikeouts — the final to Pablo Sandoval looking — to end the game for his fifth save in six games.

THE BAD

—Ketel Marte left the game Saturday with left hamstring tightness. He looked a little gimpy when he rounded first during a pop-out in his last at-bat. Lovullo said he was being further evaluated and the team pulled him as a precaution.

STAT OF THE GAME

4: It had been a day short of four months since Walker last won a game at Chase Field.

HE SAID IT

“One word: remarkable. He comes in, wants to pitch, he never wants off days. When I tell him he’s down, there’s some reluctance to his response in saying OK. But he’s a true team player and he wants the ball every day. If you’re asking me for a thought, what comes to mind is, ‘remarkable.'” — Lovullo on Rodney’s fifth save in six games

UP NEXT

The Diamondbacks close the three-game series against the Giants with a 1:10 p.m. first pitch.

Left-hander Patrick Corbin (11-11, 4.19 ERA) comes in on his hottest streak of the season. Over his last three starts, he’s allowed one earned run over 23.1 innings.

San Francisco sends right-hander Chris Stratton to the mound for his eighth appearance and fifth start of the season. He has not allowed an earned run in his last two starts (12.2 innings).

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