NY Mets ace Marcus Stroman is FURIOUS with NASCAR driver Kyle Larson for saying the n-word ... saying he should never race again and deserves to have his ass kicked.
Of course, the 27-year-old dropped an n-bomb during a virtual race on Easter Sunday ... apparently not realizing his audio was streaming out to thousands of people on Twitch.
Larson -- who later apologized for the slur -- was suspended by NASCAR, lost sponsorships, and was booted from his team.
Enter Stroman -- whose parents are black and Puerto Rican. He's so pissed off about the incident, Stro wants to throw down with Larson in the Octagon.