Brooks Koepka Goes Crazy Over Panthers' Stanley Cup Win, Ariana Grande Celebrates Too

The Florida Panthers won their first-ever Stanley Cup on Monday night, and perhaps nobody was happier to see it than golf star Brooks Koepka, who celebrated the dub with a boozy night in Nashville!!

Matthew Tkachuk, Aleksander Barkov and Sergei Bobrovsky got the job done in Sunrise ... beating the Edmonton Oilers in Game 7 of the Final, 2-1 -- and while Koepka couldn't be there in person, he certainly didn't let the moment pass by quietly while he was out in Tennessee.

Watching from a bar in the Music City, Koepka went crazy as soon as the clock hit 0:00 on the Panthers' season.

The 34-year-old -- who's from West Palm Beach, Fla. -- hugged his friends, took selfies, sang and danced ... all while slamming drinks. His wife, Jena Sims, proudly documented it all for him -- a good thing, considering there appears to be a decent chance parts of the night might be a little foggy for him on Tuesday.

The golfer, of course, wasn't the only celeb Panthers fan to bask in the glow of the win ... Ariana Grande took to her social media to show off her pride as well.

The pop singer put a heart emoji and a ton of exclamation points on footage of Bobrovsky holding Lord Stanley high.

UFC star Kamaru Usman and former Heisman Trophy winner Mark Ingram also celebrated the big win ... posting a bunch of congratulatory images on their Instagram pages.

Meanwhile, the team sure enjoyed the fruits of their labor inside Amerant Bank Arena ... dousing the Cup and each other with champagne in a wild locker room celebration.