Former UFC star Kenny Florian thinks Conor McGregor might just be the greatest of all time ... at talking smack ... saying the Irish swagmaster is the best with his mouth since Muhammad Ali.
We talked to Florian at his gym in Burbank ... and asked about McGregor's verbal antics leading up to the big UFC 196 showdown this weekend ... and Kenny -- a UFC analyst now -- had some high praise.
That's not all, Florian also expertly broke down not only the McGregor/Diaz fight .