"Hot Boy" rapper Bobby Shmurda was ice-cold to a Tampa Bay Lightning supporter during the New York Rangers game on Wednesday -- trollin' the fan by waving an NYR towel right in his face!
The hilarious moment happened during Shmurda's epic night at Madison Square Garden -- when the Brooklyn rapper was in the stands cheering his face off for the Rangers in Game 1 of the Eastern Conference Finals.
Video shows Shmurda was gettin' his dance on ... and then he turned to a TB fan sittin' right behind him, and waved a "No Quit in New York" Rangers' towel in the guy's grill.
To his credit, the fan took the trollin' in stride -- responding with nothing more than a thumbs down.
Bobby had a hell of a night during the game in between going crazy for big plays -- taking a bunch of photos with fans both inside and outside of the venue.
TMZ Sports has learned this was Bobby's first-ever hockey game ... and he attended it after getting invited by Icy Ventures -- a talent management company (founded by Josh Stone and his brother Troy Stone as well as NHL agent John Osei-Tutu) whose focus is to bring hip-hop culture to the sport.
"Bobby’s energy could not be contained," Troy told us of Shmurda's night. "Fans were shocked to see such a high-profile rap artist in the building for a Ranger game."
"Bobby was so excited he started taunting the opposing team’s fans, which lead to a viral moment which the NHL has desperately needed."
Troy added, "The experience for Bobby couldn’t have gone better as he saw the Rangers win and got to witness a real NHL fight.”
Shmurda wasn't the only rapper at MSG ... Fat Joe also pulled up in his red and blue gear supporting the Rangers -- and they both went home happy, as the Rangers won easily, 6-2.