Dana White says the fight deal he made with Floyd Mayweather was entirely constructed and sealed at the Clippers game last month ...and says they're targeting a Sept. 2020 fight date.
"He and I did a deal right there in our seats on the court," the UFC honcho told Rich Eisen ... "We shook hands and we have a deal."
White didn't reveal any details about Floyd's potential opponent -- but later told Jim Rome he's hoping to sit down with Floyd's business partner, Al Haymon, in March to get a fight booked for Sept.
As TMZ Sports previously reported, Mayweather is actually trying to book TWO comeback fights in 2020 ... both boxing matches.
Sources close to Floyd tell us ... he wants to fight a respected pro boxer (we're told he's seriously considering Manny Pacquiao) plus another match with a UFC fighter.
Floyd has previously called out Khabib Nurmagomedov, but it's unclear if that's his intended target on the UFC side of things.
Of course, we know Conor McGregor is VERY interested in a rematch ... but we don't know if the feeling is mutual.