Floyd Mayweather -- KO'S NEW ORLEANS WINE BAR ... In Super Bowl Party War

Floyd Mayweather went toe-to-toe with a New Orleans wine bar ... and kicked its whole ass ... with a judge forcing the bar to pay up for SPREADING LIES about the boxer ... TMZ Sports has learned.

We broke the story ... Mayweather sued The Wine Bistro in N.O. back in 2013 -- claiming the place falsely advertised that he'd be hosting a Super Bowl party with some members of The Money Team.

Floyd was pissed that the bar profited off his name and worried his fans would be pissed ... thinking he was a no-show.

Now, we've obtained legal docs which show the U.S. District Court judge saw it Mayweather's way -- ordering the bar to pay up.

But it wasn't exactly the MASSIVE windfall Floyd was hoping far -- he only walked away with $2,250 in damages.