Diamondbacks right-hander Zac Gallen was roughed up on Saturday night. He was bad at the beginning, a little better in the middle, then ineffective again at the end of his five-inning performance against the Seattle Mariners.

It was the first time in 25 big-league starts that an outing of his could be described in such a harsh manner. As such, despite the ugly pitching line — seven hits, seven runs, five walks — in what was a 7-3 loss to the Mariners, it is difficult to draw any broad conclusions or have any major takeaways as it relates to Gallen.

He was tremendous through the first 23 starts of his career. His 24th was terrific for five innings then fell to pieces. This one, No. 25, was a dud. It happens.

“Just wasn’t executing, really, is what it came down to,” Gallen said. “It just wasn’t a good outing.”

The loss halted the Diamondbacks’ win streak at two. It was their 18th loss in their past 22 games and dropped them to 17-30. Only three teams in baseball have worse records.

On Monday in San Francisco, Gallen was dominant through five innings. In the sixth, he did not retire any of the six batters he faced. That inning was responsible for ending what had been a record run of starts to begin a career; no one in baseball history had ever gone so long without allowing at least four runs.

But for as unexpected as the sixth inning in San Francisco was, the beginning of Saturday’s game felt just as stunning. The Mariners scored four times in the first. Ty France started it with a no-doubt home run. The Mariners then went walk, double, walk, double. Gallen couldn’t seem to stop the bleeding.

When four of the first five batters reached to open the second, Gallen had suddenly been unable to retire 15 of the previous 20 batters he had faced dating to his previous start.

“It is a total shock,” Diamondbacks manager Torey Lovullo said. “I think today was a total outlier. I know he did give up the four runs, but let’s focus what he did for the first (five) innings in San Francisco. He was practically unhittable. This one was a little uncharacteristic. There were some misfires early. And then he really had trouble getting those gears started.

“Yes, he does spoil us. I don’t think this is going to be something that lingers. I think he’s going to get back on the right track.”

Gallen said he actually was pleased with the quality of his stuff and felt good on the mound. He wondered if he felt too good. He said the front side of his delivery can occasionally get out of whack — and fly open too soon — on days when he feels that way.

“I think it just came down to my delivery,” he said. “Mechanically, I was rushing a little bit and was unable to execute some of those pitches when I wanted to.”

Gallen walked two batters in each of the first two innings and, at times, was visibly frustrated by home-plate umpire Nestor Ceja’s strike zone.

“I just thought some of those pitches were strikes,” Gallen said. “At the end of the day, the umpire didn’t call them strikes. That’s what happens. I don’t think it really affected me too much. I just wasn’t really happy, to say the least.”

Said Lovullo: “We train our guys, whether they’re hitters or pitchers, not to let those types of decisions to impact more than one pitch. I did know he was a little bit frustrated … (But) it wasn’t the reason he gave up seven runs, I know that.”

Lovullo said Gallen’s focus after the rough first inning shifted toward getting through five to at least save the bullpen, something he was able to do. He put up zeros in the third and fourth innings, but the Mariners’ Jose Marmolejos launched a two-run homer in the fifth.

“For us, it was just we needed to be stubborn,” France said. “He likes to nibble and try and get those corner calls. The more stubborn we were off of him, the harder it was for him. So just kind of shrink our zone and get something we could do some damage with and kind of lay off the other stuff and I think it helped out tonight.”