"I think it's gonna be just a big s**t show."
Gotta appreciate the honesty from Andre Berto -- who tells TMZ Sports he doesn't exactly have high expectations for the big Floyd Mayweather vs. Logan Paul fight on Sunday.
Look, Berto -- a very accomplished and well respected boxer -- has actually been in the ring with Mayweather in 2015 ... and knows what's like to fight against the best in the world.