PHOENIX -- Asked about Zac Gallen this past week, D-backs pitching coach Matt Herges said the word was out around baseball that the right-hander was someone to be reckoned with and planned for.

"The talent level Zac has, teams have to bear down," Herges said. "They have to go up with a plan. And I don't think there's a secret about what he tries to do, how he gets people out."

Gallen has hit the first somewhat rough stretch in his career. He fell to 1-7 on the year after the Padres beat him 8-2 on Sunday afternoon at Chase Field.

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After coming to Arizona before the Trade Deadline in 2019, Gallen was practically unhittable while setting a Major League record from 2019-20 by allowing three or fewer earned runs in his first 23 big league starts.

This year, he has allowed more than three runs in five of his starts, including Sunday, when he gave up four on eight hits over five innings.

"Obviously, when you compare it to the record, it's going to be unusual," Gallen said of his struggles. "But I mean this ultimately comes down to making some mistakes in counts where I probably don't make those mistakes last year.

Really, it's just the consistency. It's been a good start here, then not so great start there."

Fernando Tatis Jr., who was activated off the injured list before the game, did a lot of the damage against Gallen, collecting a double and a pair of solo homers against him.

"Un-Zac-like," D-backs manager Torey Lovullo said of the outing. "There were eight hits, and I think [11] total baserunners. That's not who he is. I know that. He's aware of that. I know he's going to just come out pounding away on it for the next several days to make his next start as good as could possibly be.

“It's an easy bet to say that he's going to figure things out or attempt to figure some things out. There have been some tough outings, but when he does it right, he carries us deep into the ballgame and allows very few opportunities, very few baserunners with very few run-scoring opportunities."

Gallen is a key part of the D-backs’ rotation -- not just this year but going forward.

When the team looks at which players it wants to build around, Gallen is at the top of the list on the pitching side, so getting him right over the final six weeks is a high priority.

And there is no one more aware of that than Gallen, who is an extreme competitor. Even when he was in the midst of his record-breaking streak, he was constantly tinkering and trying to find ways he could get better.

"It's like any other pitcher, the hitters, the hitting coach, whoever puts those plans together is going to dissect how you successfully get people out," Gallen said. "That happens to any pitcher, anybody that's been around for a while. … The greats, the Kershaws, the deGroms -- they have to kind of flip the script, kind of take a step back and self-evaluate what you do successfully and how teams might approach you."

The National League has adjusted to Gallen. Now it's his turn.