
18. Losing to Khabib Nurmagamedov
After all the toxic build-up and venom, Khabib won their anticipated fight at 2018’s UFC 229. This was by far the worst of his losses because there could be no excuses. The champion put him under relentless pressure from beginning to end. Then he tapped out in the fourth round. Fans sneered ‘McTapout’ for his shoddy ground game.

But the worst part of the fight was in the second round. This was when Nurmagamedov put the beating of McGregor’s life on him. Khabib told McGregor repeatedly, “let’s talk now.” The Notorious was mortified and exposed in front of the entire world. In short, this loss could prove to be career-defining.