TAMPA, Fla. -- As the sun set on a chilly Saturday evening in South Tampa, Pete Alonso stepped into the batter’s box and launched baseball after baseball out of Plant High School’s field and toward the school building beyond the left-field fence. The emcee, DJ Fresh, rattled off numbers that wouldn’t have been out of place in one of Alonso’s two Home Run Derby victories: moonshots that sailed 417 feet and came off his bat at 116 mph.

This show of power was a little different for the Mets’ two-time All-Star slugger, however. It was the final, crowd-pleasing act of his first annual Battle for the Bay, a homer-filled event at his alma mater to benefit the Alonso Foundation and give back to his hometown.

Hundreds of people flocked to Plant High on Saturday afternoon for hours of food trucks, games and activities and, above all, dingers. Alonso and his wife, Haley, created an event fittingly focused on home run derbies. Some of the Tampa Bay area’s best youth baseball and softball players, from ages 12 to 16, went toe to toe before clearing the way for a round of big league batting practice.

“Obviously, I've participated in the Major League Home Run Derby. It's a blast. But also, growing up, as a kid, I did a couple, and I always thought it was an extremely fun event,” Alonso said beforehand. “I'm just really happy that we get to put this together for some kids. … We have some of the best talent in the Tampa Bay area, so for them to be able to show it off, especially with a bunch of people here, it's going to be a really fun time.”

Alonso bounced around the field during the early rounds, spending time with kids, parents, coaches and fans. (He also occasionally gravitated toward a special guest, a service-dog-in-training from K9s For Warriors; he and Haley named the dog Bear.) When they were done, Alonso presented each winner with a signed chrome bat and baseball -- plus custom home run chains of their own.

Then, out came Alonso and some Major League friends for a miniature derby of their own. Angels infielder Gio Urshela, Astros outfielder Kyle Tucker (a Plant alumnus like Alonso) and Red Sox infielder Christian Arroyo (also a Tampa native) joined former Cleveland slugger Travis Hafner and former Rays All-Star/current MLB Network analyst Carlos Peña before Alonso capped his own event with authority.

Orioles reliever Mychal Givens, a Tampa native and Plant alum, was also in attendance. And former big leaguer Xavier Scruggs, an ESPN and MLB Network analyst, served as a sideline reporter, interviewing the Little Leaguers and big leaguers after they hit.

“It means a lot,” Alonso said. “It's great that people are willing to donate their time and talent and come and help support.”

In turn, Alonso is helping support baseball in Tampa. All the proceeds from Saturday’s event will be put into grants through the city of Tampa to restore and refurbish youth fields. Noting the role baseball always played in his life, the 28-year-old stressed the importance of maintaining clean, safe fields for kids in his hometown.

“I just want to show the Tampa community, it's like, 'Hey, listen, I haven't forgotten where I came from, and I just want to be able to give back,’” Alonso said. “It's really fitting that we're doing a home run derby or a baseball event. Tampa is just very rich in baseball history, and there's so many amazing players that were born and raised here and have made big names for themselves.”

Alonso is now one of them, and the day before his Battle for the Bay brought another reminder. He agreed on Friday to a $14.5 million deal for this season to avoid arbitration, the largest single-season salary given to an arb-eligible first baseman.

“It was really special. As a young kid, thinking back on it, I never thought that that would be a possibility. I mean, it was a dream,” he said. “Especially as a young kid … you just want to get there, and then once things start to become more of a reality, then it's like, 'OK, this is real. This is real.' It was a really special moment.”

So was Saturday.

“I've created amazing memories and relationships playing, and some of my best memories are from when I was a kid. That's where my love of the game was really started,” Alonso said. “Here in Tampa, baseball means a lot, and it means a lot to me. Hopefully, we can get some kids to fall in love with the sport.”