The McGregor vs. Mayweather madness has gone EAST -- with the two about to clash for the 3rd time in Brooklyn ... and we're live streaming the entire thing.
Mayweather made a pit stop at the bank earlier in the day -- so expect the cash to fly.
Meanwhile, Conor's been spotted around NYC in a convertible ... without his shirt.
What'll happen when they face off onstage? Who the hell knows. But it'll be entertaining.
It's scheduled to kick off at 3:30 PM PT at the Barclays Center .