3 times Conor McGregor was wrong as Mystic Mac

3. Conor McGregor vs. Floyd Mayweather

During a press conference in Los Angeles, McGregor confidently announced that he was going to knock Floyd Mayweather out "inside four rounds." A couple of days later, he predicted that it would be an uppercut or a hook while speaking with Fight Hub TV.

With 10 days remaining before the money fight, the Nevada State Athletic Commission approved Mayweather's request to allow eight-ounce gloves instead of 10 ounces. Team McGregor had agreed to the change as well.

Given that 8-ounce gloves were a notch closer to the four-ounce gloves usually worn for MMA fights, McGregor felt quite comfortable with the decision and even changed his prediction based on it.

"I believe now with the gloves at eight ounces, I don't believe he makes it out of the second round," McGregor said in a media call later that day. "Part of me wants to show some skill and dismantle him that way. But I do not see him absorbing the blows in the first two rounds."

The UFC megastar failed to deliver on his promise and ceded to the undefeated boxer via technical knockout in the 10th round. Despite the defeat, McGregor is to date hailed by combat sports entities, including boxing legend Mike Tyson, for lasting ten rounds against Floyd Mayweather.