PHOENIX -- Tough outings have been rare for Zac Gallen since he joined the D-backs at the 2019 Trade Deadline. When the right-hander takes the mound, Arizona can typically expect at least a quality outing, if not a special start.

But over the course of a 162-game season, pitchers are going to have off nights. Even Gallen, who allowed four runs in four innings and couldn’t find his rhythm during a 14-6 loss to the Rockies on Saturday night at Chase Field. It was only the third time in 31 career starts that Gallen allowed more than three runs, as he labored through a 93-pitch outing.

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“I’ll categorize, any loss stinks. I’m not saying we’re all Zac watching and we’re going to expect to win every single game that he pitches,” Arizona manager Torey Lovullo said. “We expect to win any game that any of our starters go out there and pitch. It's probably something that we get conditioned to, but by no means are we going to rely on Zac to go out there and throw a one-hitter or no-hitter and put it all on his shoulders.”

In his previous outing last Sunday, Gallen had thrown a one-hitter during an impressive seven-inning complete game at Atlanta. He needed only 83 pitches to carve through the Braves’ lineup, lowering his ERA to 2.16 through three outings after his season had gotten off to a late start due to a hairline stress fracture in his right forearm.

But this time out, Gallen had no clean innings against a Rockies lineup that consistently had a bunch of traffic on the bases. Most of the damage came in the fourth, when Gallen couldn’t preserve the D-backs’ early 2-1 lead. Raimel Tapia tied the game on an RBI single and Ryan McMahon put Colorado on top, 4-2, with a two-run single.

“It's not necessarily a thing whether I throw well or poor the time before, it isn't going to make it more or less frustrating,” Gallen said. “Whether I'm throwing five in a row that were good or five in a row that weren't good, not performing well is going to suck just as much.”

The only other times that Gallen has allowed more than three runs in a start came in consecutive outings late in 2020. He gave up four runs to the Giants on Sept. 7, then allowed a career-high seven runs against the Mariners five days later. Those were his only losses last season.

Even with the rare tough outings, Gallen continues his research to try to find what may have gone wrong. But he isn’t going to dwell on the less-than-ideal results.

“I usually go by the one-shower rule, at least the one-sleep rule -- once I go to bed and wake up in the morning, I’ll flush it,” Gallen said. “Doesn’t mean I won’t watch the game again and pick up on different things, but once I shower after the game, that flushes most of it. Watch the game tonight, when I wake up tomorrow, it’s a new day.”

Several D-backs pitchers may share that mindset after Saturday’s game. Each of the first four hurlers that Arizona used allowed at least one run. The only two players who took the mound and had clean outings were infielders Asdrúbal Cabrera and Wyatt Mathisen, after the game was well out of reach.

Left-hander Caleb Smith, who was moved to the bullpen after his first start of the season, had allowed only one run in 12 2/3 innings over his first eight relief appearances. After the D-backs cut the Rockies’ lead to 4-3 on a Carson Kelly RBI single in the fifth, Smith gave up a two-run homer to Trevor Story in the sixth.

Arizona then never got closer than two runs, and Colorado broke the game open with a seven-run eighth.

“Offense has been hot, didn't really give them a chance to come in in the inning and do some damage, always felt like they were trying to claw back for one, two, whatever,” Gallen said. “At the same time, the morale in there is still high. We're still playing well. I don't think guys are wary. We're just going to show up tomorrow and keep doing what we're doing.”