In a way, the struggles of Zac Gallen in his past two starts show just how amazing he was over his first 23 Major League starts when he made pitching look easy.

Gallen allowed four runs in the first inning and seven overall as the D-backs fell to the Mariners, 7-3, on Saturday at Chase Field.

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

It was shocking, is what it was, given the way Gallen had pitched since reaching the Majors. The 25-year-old opened his big league career with 23 straight starts in which he did not allow more than three runs in a game, snapping Aaron Sele’s record. The streak ended in his last start, when he allowed four runs in the sixth inning against the Giants, but it wasn’t until Friday when he truly had a poor outing.

“It is a total shock,” D-backs manager Torey Lovullo said. “I think today was a total outlier. I know he did give up the four runs [against the Giants], 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 he had trouble getting those gears started early.”

The Mariners clearly had a gameplan against Gallen -- they weren’t going to chase outside the strike zone.

In the first inning, Ty France hit a one-out homer and the Mariners drew a pair of walks, both of which came around to score.

When Gallen is at his best, his cut fastball gets hitters to chase just off the corner, and his changeup dives just out of the bottom of the zone, causing hitters to swing and miss. That didn’t happen much early on Saturday, as he only got two whiffs on his changeup in the first.

“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.”

The “corner calls” that France referred to did not go Gallen’s way Saturday, and his frustration was evident throughout his outing.

“I mean, 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.”

What Gallen said impacted him more were his mechanics, which for the second start weren’t in sync.

“Probably was rushing a little bit with my front side,” Gallen said. “I felt really good. Maybe a little bit too good. I think it just came down to my delivery. Mechanically, I was rushing a little bit and was unable to execute some of those pitches when I wanted to.”

Gallen still found a way to make it through five innings to spare the bullpen, something he and Lovullo discussed in the dugout after the rough first inning.

Don’t look for Gallen to take any different approach between starts after this outing as opposed to the more successful ones. As his teammates will attest, Gallen is a perfectionist who is always working to try and find something to get better at between starts.

“I’m going to put just as much work in whether I went out and threw seven [innings] and gave up [zero runs], as opposed to today,” Gallen said. “It’s not going to change how much work or effort I put in in between starts.”