LOS ANGELES -- As August nears its end and the National League Wild Card race heats up, every game and every performance feels magnified. That goes double for an ace.

And Monday at Dodger Stadium was an atypically rough night for right-hander Zac Gallen, who was tagged for a season-high six earned runs while surrendering a career-high four homers as the D-backs dropped the series opener to the Dodgers, 7-4.

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“I think there were some uncharacteristic fastball misses for him,” said D-backs manager Torey Lovullo. “Usually, he's just spot on with his command. That's what I saw. And he made a couple mistakes to some good hitters, and they hit some home runs.

“You don't really see Zac give up a lot of home runs. But I just think there were some mistakes in the middle of the zone and they took advantage of it.”

One of those misses came to the second batter Gallen faced. He left a four-seamer over the middle of the plate for Freddie Freeman. Two batters later, Max Muncy knocked a hanging knuckle-curve into the right-center-field stands, putting the D-backs in an early 3-0 hole. And though from there Gallen retired the next eight batters he faced, he never quite seemed to settle in.

In the bottom of the fourth, Gallen allowed a leadoff single -- which was erased by a double play -- before walking a pair, whom he ultimately stranded. In the fifth, he got out of a first-and-third situation with a strikeout, one of just three on the night for the usually prolific punchout artist.

The sixth inning is where things truly unraveled. Arizona entered the frame up by a run, but former D-backs teammate David Peralta greeted Gallen with a single, followed by Jason Heyward and James Outman launching back-to-back homers. Suddenly, the D-backs found themselves trailing by two -- and, as it turned out, down for good.

Gallen got one more strikeout, but his night came to an end after he gave up a single to No. 9 hitter Michael Busch. Gallen allowed a total of nine hits and three walks, both one shy of his season highs. His stuff was less deceptive than usual, too, as he registered just six whiffs in 101 pitches.

“I felt solid, bullpen felt really sharp, playing catch felt sharp,” said Gallen. “I just didn't really execute. It’s not like I went into that game feeling like I didn’t feel great, which is probably the most frustrating part. If I would’ve felt bad, just like, ‘Whatever, I can grind it out.’ But, yeah, I mean, I feel like I could have had a better outing. So it's frustrating.”

Bad nights can happen to anyone, even an NL Cy Young Award candidate like Gallen, who has been nothing short of reliable this season. His ability to limit the long ball, in particular, has been one of his hallmarks. Prior to Monday, he was allowing homers at a rate of 0.9 per nine innings, which ranked fifth among qualified NL starters. He had surrendered three home runs in a game just twice in his MLB career (Sept. 15, 2019, vs. the Reds and Aug. 15, 2021, vs. the Padres).

Precedent certainly suggests this should be a blip for Gallen, a 2023 NL All-Star who’s tied for second in the NL with 17 quality starts. In the rare instances where he has struggled, more often than not he’s bounced back with a strong performance his next time out. Now more than ever, the D-backs are going to need him to do that when his turn in the rotation comes up again -- likely this weekend at home against the AL East-leading Orioles.

With the loss, Arizona’s hold on the third NL Wild Card spot dropped to half a game over the Giants, who beat the Reds in the first of three meetings in San Francisco. Cincinnati remains 1 1/2 games behind the D-backs, who remain a half-game behind the Cubs, who occupy the second spot.