SAN DIEGO -- MacKenzie Gore believes he accomplished his goal of becoming the best player in the country, so he's progressed to his next one: making it to San Diego and helping the Padres to a World Series title.

On Saturday, the Padres signed Gore, the No. 3 overall pick in the 2017 Draft. He was then introduced at Petco Park, joined by general manager A.J. Preller, director of scouting Mark Conner and agent Scott Boras. The bonus for the high-school left-hander from Whiteville, N.C., is a slightly over-slot $6.7 million, a source told MLB.com's Jim Callis.

Gore, an East Carolina University commit, pitched at Petco Park in the 2016 Perfect Game All-American Classic in August, allowing a pair of runs in his one inning. He first came to San Diego in August wanting to be the top amateur but left knowing he needed to improve to ascend to that title.

By the time his senior season at Whiteville High School arrived, he'd certainly done that. With a mid-to-high-90s fastball and plus-curveball, not to mention a massive leg kick, Gore struck out 158 and walked only five in 74 1/3 innings, posting a 0.19 ERA to earn 2016-17 Gatorade National Player of the Year honors.

"My goal was always to be the best player in the country, so in the offseason, I worked hard and got a lot stronger," Gore said. "Now I feel like, not in a cocky way, but I am the best player in the country."

Padres area scout Nick Brannon first saw Gore at an workout in June 2016. Early this season, Preller attended one of his games. A week later, Preller, director of pro scouting Logan White, scouting special assistant David Post and other members of the Padres' front office met with Gore.

His arm had already made an impression; his personality did the same.

"It's very rare that you see players that excite you," Preller said. "You left that game that day, and we couldn't stop talking about him, honestly.

"A week later, we had an opportunity to sit down with his family, sit down with him and kind of hit him between the eyes and find out what he was truly about. … We left that meeting, we were probably high-fiving in the parking lot."

Gore's parents, sisters and high school pitching coach joined him for Saturday's news conference. Preller and Conner praised his parents for their work in raising him, a point Boras echoed.

"Who he is as a person, how he takes information, and how he responds to competitive stimulus, how he responds to not being the best at the moment but knows how to get to be the best later on -- that's where he is now," Boras said. "He's jumped up to being one of the top arms.

"... The idea, I think, with this organization is, kind of like when you fly over an island and you see a big mountain and you think it's a mountain. But I think San Diego is going to be a volcano, because there's a lot underneath that's coming. MacKenzie is going to a principal part of it."

Preller said Gore will head to Arizona on Sunday to begin a throwing program before joining one of San Diego's two Arizona Rookie League teams. Preller said Gore pitched 20-30 innings last summer and will throw about the same in Arizona.

After the news conference, during which Gore donned a Padres jersey and cap, he and his family headed out to the field. Gore made it back to Petco Park. He had no plans on it being his last visit.

"I'm really excited to be a part of this organization," Gore said. "There's a lot of young players. I'm ready to get up here and win a World Series."

Nathan Ruiz is a reporter for MLB.com based in San Diego.