SAN DIEGO -- It's a sunny Sunday afternoon at Petco Park in 2022, and a 23-year-old MacKenzie Gore is carving up opposing hitters, looking every bit the ace-caliber starter the Padres always envisioned.

That’s certainly how they drew it up half a decade ago. And now that it's a reality, the roundabout path Gore took to get here feels sort of moot. So he struggled for a couple of seasons while the pandemic wreaked havoc on his development. So what?

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Gore is in the big leagues now, and it sure looks like the lefty is here to stay. Through eight outings, he owns a 1.71 ERA and is the presumptive early favorite for the National League Rookie of the Year Award. On Sunday afternoon, Gore delivered his best start yet, pitching seven scoreless innings before Trent Grisham clanged a walk-off home run off the right-field foul pole to seal a 4-2 victory over the Pirates in 10 innings.

“Man, he is some kinda good,” Padres manager Bob Melvin said of Gore. “Seems like he’s even getting more economical. Now he’s throwing strikes, he’s getting deeper in games, where we can mentally push him a little bit farther. He pitched out of the bullpen one time. I don’t know how much more you can ask out of him.”

The Padres have envisioned big things for Gore since the night they drafted him third overall in 2017. By the end of the '19 season, he was the consensus top pitching prospect in baseball. Then came the struggles, the setbacks, the utter inability for Gore to command his fastball and to repeat his mechanics.

The circumstances were unprecedented, of course. He spent 2020 pitching at an alternate training site amid the height of the pandemic. That’s when things began unraveling on him. It took a year and a half for Gore to put it all back together. But he is quick to say that he’s better off for it.

“Going through what I went through, it just makes it where you’re much more comfortable now,” Gore said. “The more I pitch up here, the more comfortable I get.”

Gore, who hadn’t completed six innings until his most recent start, cruised through seven on Sunday. He struck out nine and allowed only two hits. It wasn’t unreasonable to think he might get the eighth.

“We always want to go a little longer,” Gore said with a wry grin.

“I told him after the seventh, ‘You’ll see some 9s at some point in time if you pitch economically like this,’” Melvin said.

Melvin instead called for Nabil Crismatt, who surrendered two runs in the eighth as the Pirates tied the game. That set the stage for Grisham’s walk-off heroics two innings later.

With the automatic runner at second base, Grisham twice squared to bunt, but Pirates right-hander Chris Stratton threw both pitches outside the strike zone. Having worked himself a favorable 2-0 count, Grisham got the green light to swing away. He made the most of it, turning on a poorly placed fastball from Stratton. As the ball hooked into the right-field corner, Grisham stood frozen in the batter’s box, willing the ball fair.

“I figured it was foul,” Grisham said. “I was just sitting there waiting to see if it hit the foul pole or not.”

“I’m a little surprised he actually swung,” said Pirates manager Derek Shelton. “He’s probably one of the better bunters in the game. But it got taken off, and he ended up hitting the ball out of the ballpark.”

It was Grisham’s second walk-off homer for the Padres. (And, strangely enough, his first at Petco Park. He walked off the Giants in San Francisco in 2020 after a pandemic-related cancellation forced the Padres to play a home game at Oracle Park.)

The walk-off also gave the Padres their 30th victory of the season, tying a franchise record for the fewest number of games to reach that mark. They did so during their 1998 pennant-winning campaign and during each of the past two seasons as well.

Of course, the 2020 and '21 seasons unraveled -- at different stages -- in part because the Padres were short on starting pitching. This year, they might have the deepest group of starters in baseball. Gore’s emergence is a big part of the reason why.

“He’s just doing it with a lot of confidence,” Melvin said. “He’s back to where he was when he signed. … More than anything, it’s just the calmness and the way he goes about his business.”

Indeed, MacKenzie Gore is back. So, too, are the Padres’ long-term visions of a rotation with Gore at the center of it.