PORT ST. LUCIE — Kyle Tucker and Pete Alonso were opponents earlier this week, but they already have begun looking forward to next week, when they will unite for Team USA in the World Baseball Classic.

It will be a sense of back to the future for both, who spent two years as teammates at Plant High School in Tampa.

Alonso, the Mets’ first baseman, is two years older than Tucker, an outfielder for the Astros.

“Pete is still one of the best hitters in the game and he was just like that in high school,” Tucker said. “In high school, you could tell he was a real good player, but he was more of a raw player, but he just worked so hard at his game and he loves this game and that is why he wants to be one of the better players in the league.

“He works so hard and that is what is going on here.”

Tucker won a World Series title last season with the Astros.

The right fielder also received a Gold Glove award and was selected to his first All-Star team.

Alonso reached 40 homers for the second time in his career in 2022 and was a centerpiece for a Mets team that won 101 games before losing to the Padres in the NL wild-card round.

“I pretty much kept up with [Alonso] after high school,” Tucker said. “He’s in the headlines every other day now, especially being here with the Mets, but he was one of the best players in college, back at Florida, and he is one of the best players now, so you see a lot of stuff with him in the news and stuff because he is doing so well, but with his work ethic he’s definitely earned it.”

Alonso mentioned his anticipation of playing in the same lineup as Tucker, but also is enamored with the idea of playing on the same team as Paul Goldschmidt, the 2022 National League MVP.

Jeff McNeil, Adam Ottavino and Brooks Raley are the other Mets headed to Phoenix on Monday to begin workouts for Team USA.

“I get to reunite with my high school teammate and we get to represent our country,” Alonso said. “To go with Jeff, Otto and Brooks … and to play with Paul Goldschmidt, there’s not really a scenario where me and him would be on the same team, but to be able to actually be on the same squad and working toward the same goal, to me that is exciting and special because there is no real scenario where that could happen.”

McNeil, who like Alonso will be participating in the tournament for the first time, said he is looking forward to being teammates with Mike Trout and Mookie Betts.

“I got to play against Trout last year, so that was the first time I saw him play live, on the same field as him,” McNeil said. “It’s going to be cool to be teammates with him and watch him up close.”

Ottavino, who pitched for Team Italy in 2009, was asked about the further bond among Mets teammates that could form within the context of representing the United States.

“The group of us are obviously going to travel together there and back and initially when you are with a new group of people you are going to gravitate toward the people you already know, so I do think it might be the case,” Ottavino said.

Alonso highlighted the “Group of Death” — Puerto Rico, Venezuela and the Dominican Republic are in the Miami bracket — as teams to beat, along with the U.S. and Japan.

“This is the World Cup of baseball,” Alonso said. “This is a great chance to grow the game — and this is a worldwide game anyway, but to be able to showcase the game to multiple countries, it is really exciting.”