DENVER -- There would be no miracle Coors Field comeback this time -- despite the best efforts of the San Diego offense.

Just another Padres starter left to ponder pitching in a ballpark that seems to laugh at the very idea.

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Joey Lucchesi entered Friday night riding a four-start stretch in which he’d posted a 1.57 ERA. He blanked the Rockies for six innings in his last outing, and he’d asserted himself as one of San Diego’s most reliable starters.

Then he arrived in Colorado, and he endured the worst start of his big league career. Lucchesi allowed eight runs on nine hits, as the Padres dropped the series opener, 10-8. He allowed more home runs (three) than he recorded strikeouts (two). And all of that damage came in a span of just 45 pitches.

“I came here with confidence,” Lucchesi said. “I thought I was going to deal. I've felt super comfortable here, and I thought it was going to go my way. It didn't.”

If anyone should’ve been comfortable in Colorado, it’s Lucchesi, who had posted a 1.56 ERA in three starts here. But he struggled from the outset. Nolan Arenado launched an opposite-field two-run shot in the first. Three innings later, the Rockies would rally for five runs, chasing Lucchesi after just 3 1/3 innings.

In some ways, it was a continuation of the Padres’ last trip here. In June, the two clubs combined for a record-setting 92 runs in a four-game series. At the time, two improbable ninth-inning Padres comebacks overshadowed the rotation’s issues.

But those struggles are very real. That weekend, San Diego starters allowed 24 runs in 12 1/3 innings. Lucchesi continued the trend on Friday night.

“It can be tough sometimes,” said Padres manager Andy Green. “You've got to go out and hit your spots, and you've got to get some swing-and-miss. Joey struggled to find the swing-and-miss.”

The Padres’ rotation is filled with young starters -- including Lucchesi -- who have several years of Coors Field starts ahead of them. Right now, they’re still trying to solve the puzzle.

“The main message ... is you've just got to treat it like a normal game,” catcher Austin Hedges said on Friday afternoon. “If you start thinking about where you are, and you give up some cheap hits, some cheap homers, you start feeling bad for yourself. That's when teams start scoring 15 runs. The guys that treat it like a normal game, those are the guys that go out here and have success.”

Lucchesi is the lone starter on the staff who has had any measure of success here in the past. But on Friday, the movement on his sinker was nowhere to be found. The Rockies capitalized, and they led, 8-2, at the time of Lucchesi’s exit.

The Padres stormed back with a five-run sixth, sparked by Wil Myers, who finished with two hits and a walk. Josh Naylor and Luis Urias also had two hits apiece.

For a moment, it felt reminiscent of that wacky June series, in which the Padres rallied from a seven-run deficit and a five-run deficit for their two victories. Given the history, a six-run comeback seemed entirely possible.

“Good battle from the offense,” Green said. “They put us in position to be right there. We had some really good opportunities, got contributions up and down the lineup. We were just searching for that last big hit to put us ahead.”

Unlike the Padres' last trip here, that last big hit was nowhere to be found.