TMZ has obtained video of Isaiah Washington dropping the f-bomb ... yes, that f-bomb.
Reports say that Washington called Knight a "faggot" on the set of the popular show -- a claim Isaiah flat-out denied in the press room at the Golden Globes on Monday. "No, I did not call T.R. a faggot, never happened," said Washington at the podium.
"Grey's" creator Shonda Rhimes tried to deflect attention from the fight saying, "I don't think any reporter made it up. We're just excited we won the Golden Globe."
Knight isn't staying silent. On "The Ellen DeGeneres Show" yesterday, he said he was shocked by Isaiah's denial, adding,"Everyone heard it ... I was under no delusions."