Despite just turning 18 this month, Tai Peete has already played in a lot of important baseball games. He starred in the 2018 Little League World Series and played on the Team USA circuit before the Mariners drafted him 30th overall in July.

But none of those games can compare to what he did for Single-A Modesto on Sunday night.

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With the Nuts trailing by as many as eight runs to the San Jose Giants, Peete hit two grand slams to lead Modesto to a 13-12 extra-inning win that completed a six-game sweep at Excite Ballpark.

They were the first two home runs of his nascent professional career. And they were also his first multihomer game of any kind.

"The first one, I saw [right-hander Luis Moreno] shook off, so I'm usually expecting something here. I got a good barrel to it," said the Mariners' 10th-ranked prospect. "After I got that one, my second at-bat afterwards [against lefty Tommy Kane], I was just thinking, 'base hit.' I don't want to do too much. But in the back of my mind, I'm just thinking, 'Swing out your shoes. Might as well. The time is now to do it. Might as well swing out your shoes.' That's what I did, and my team had my back on it. It's a moment I'll probably never forget. … Nothing really compares to what just happened."

Peete was well-known for his power heading into the 2023 Draft and had bat speed on par with any prep hitter in his class. The Georgia native put on a power display in the MLB Draft Combine too, but most of his success in pro ball before Sunday revolved more around consistency than power.

After going 13-for 37 (.351) with a triple and a double in the Rookie-level Arizona Complex League, Peete quickly earned a promotion to Single-A. He picked up five hits in his first three Modesto games, two of which were doubles.

To see him tap into his above-average power on the field in such dramatic fashion was a welcome sight for Modesto and Seattle.

"He's been awesome," Nuts manager Zach Vincej said. "He's bringing a lot of energy for us. He seems like he's very in tune with what he needs to do at the plate. He has a good approach. He's the kind of guy that's going to find barrels and can put the ball in play. He's been fun to watch the last few days."

With only 12 more games left in the California League's regular season, Peete doesn't have any more on-field goals for his first professional season. But he's learning a lot about the value of building routines, from morning schedules to pregame work to recovery.

Vincej likes to remind his players, who are playing in full-season ball for the first time, that he's not worried about results. The organization has shown its high regard for Peete, from how highly he was drafted to how quickly he was promoted. Vincej wants to see players working hard and being good teammates -- although a pair of grand slams doesn't hurt either.

"I like it here," Peete said. "Especially doing it with some of my close friends. I'm growing relationships, and one of the more important things is establishing good relationships with your teammates. On the baseball side of it, everything from here just gets easier. You start moving up and you start getting in routines, getting more consistent, that's something I'm for sure working on as I go up."