Brock Lesnar's appearance in the UFC left no room for fence sitters. UFC fans either embraced the former WWE champion, enjoying his over-the-top persona and oversized corn-fed biceps, or they rejected him outright because of his time spent faking it in front of the whole world.
There was no middle ground as Lesnar lassoed Heath Herring like he was a bucking bronco or yelled at Frank Mir and let the UFC's biggest sponsor have it with both barrels. You either loved Lesnar or hated him.
In the case of UFC champions, fans usually have a baseline level of respect. There are very few Lesnars, because the guys who make it to the top don't catapult there from out of nowhere like Brock. One exception I remember vividly is welterweight champion Matt Serra, who played up the brash New Yorker part of his personality to the hilt before his UFC 83 showdown with Georges St-Pierre.
St-Pierre was beloved in his hometown of Montreal where the fight took place, so when Serra took the cage after months insulting the local hero, it exploded in boos. That was hate, unfiltered and pure.
The third champion that comes to mind is Tim Sylvia. He wasn't loathed the way Tito Ortiz was. Ortiz, whether flipping Ken Shamrock the bird or taunting Chuck Liddell, was consistently insufferable.
Sylvia was different. Fans just kind of wanted him to go away. He was tall, awkward and lumbering and simply didn't do anything particularly well. When he was dethroned once and for all, by the great Randy Couture, it was like a burden was lifted off fandom's collective shoulders.
Have a fighter in mind who could really grind your gears? Let me know about it in the comments.