The ball landed in the part of the park that has a sign that measures 502 feet.
Stanton is one of the strongest players in the game.
The 22-year-old's batting-practice drives are often talked about by players and fans who watch the Marlins warm up. Recently, when the Red Sox were in Miami, Cody Ross, formerly with the Marlins, gathered a couple of Boston players in the dugout to watch Stanton take batting practice.
Soon, the rest of the league and an international audience will get a glimpse at Stanton's immense power.
On Wednesday, Stanton confirmed to reporters coming off the field after batting practice that he has accepted an invitation to represent the National League in the Home Run Derby on July 9 at Kauffman Stadium in Kansas City. The Derby will be televised live at 8 p.m. ET on ESPN.
One Marlins coach already is volunteering to pitch to him.
"I'm hoping he asks me," third-base coach Joe Espada said.
Espada regularly throws batting practice, and he's surrendered numerous tape-measured shots to Stanton.
Stanton also has a chance to be selected to the All-Star Game. The slugger is batting .274 with 17 home runs and 46 RBIs.
On Tuesday night, Stanton belted a home run to center field off St. Louis' Kyle Lohse that was estimated at 454 feet.
Dodgers outfielder Matt Kemp is the National League's Home Run Derby captain. He recently extended the invitation to Stanton.
Robinson Cano of the Yankees is the American League captain.