JUPITER, Fla. — Francisco Lindor and Pete Alonso headed to the World Baseball Classic in style on Sunday, as they both homered in their final Grapefruit League game with the Mets, a 7-1 win over St. Louis at Roger Dean Stadium.

“I feel like I’m in a pretty decent spot, that I’m swinging at the right stuff and my swing decisions have been pretty consistent,’’ Alonso said before departing to play for Team USA for the first time in his career. “Hopefully, I’ll help the U.S. win a championship. It’s gonna be a really fun time. I’m stoked.”

Jeff McNeil also added a single and the trio of veteran infielders are all in good form this spring, according to Buck Showalter.

“All those guys are definitely ready to go,’’ Showalter said.

He pointed to Lindor’s homer into the wind from the right side in the top of the first, calling it “well hit. Frankie is in midseason form.”

McNeil, Showalter said, “had a couple good swings” and Alonso “left us with a smile.”

The key will be getting them back healthy and still playing well as the regular season approaches.

In the meantime, they are looking forward to representing their homelands, with McNeil joining Alonso on Team USA and Lindor playing on Team Puerto Rico.

“Whenever I get to put that uniform on, I feel very proud,’’ said Lindor, who added he expected a festive attitude around Team Puerto Rico.

“The passion we have for the game is special,’’ Lindor said. “There are two things that unite the world: sports and music.”

Unlike Lindor, Alonso has never taken part in the WBC.

“I don’t know what to expect,’’ Alonso said. “It will be a ton of fun and hopefully we win some ballgames. It’s a really special opportunity. It’s not every day somebody gets a chance to represent the U.S.”

Alonso said he previously tried out for the 18-and-under team when he was in high school, but didn’t make the cut.

“I’d much rather make this one than the one in high school,’’ said Alonso, who will be playing with high school teammate Kyle Tucker of the Astros on Team USA. “This is really darn cool.’’

Eduardo Escobar and Omar Narvaez are among the other position players departing, as are pitchers Edwin Diaz and Adam Ottavino.

Jose Quintana is scheduled to pitch, but he suffered left side tightness during his outing on Sunday, so his status for the tournament may be in doubt.

Showalter hopes they all do well and have success in the tournament, but is already looking forward to their return and how to reintegrate them into the lineup without wearing them down.

“It’s going to be a long time without them,’’ Showalter said.