The very name of the man is a powerful and polarizing force in the MMA world.
Critics of Lesnar point to his inexperience and lack of technical skill. They would say his post-fight interview after beating Frank Mir, a WWE-style rant, is an example of his unprofessional attitude.
Fans of Lesnar point to his brute strength, wrestling ability and dominating performances.
Half of any crowd watching his fights wants to see him lose while the other half wants to see him dominate. Either way, the heavyweight champion is one of the biggest draws in the UFC.
The news that broke over the weekend, on the heels of the very successful UFC 104 pay-per-view, that Lesnar would withdraw from UFC 106 because of illness came as a huge surprise to MMA fans. But what does it really mean for the UFC?
Right now, the UFC is enjoying a dominant position in MMA. Most of the best fighters according to every recognized ranking system are fighting in the UFC.
The true cost of the Brock Lesnar withdrawal will be its effect on the UFC 106 pay-per-view. The polarization Lesnar's presence causes along with his WWE fan base translates into big draws.
The Forest Griffen versus Tito Ortiz match promises to be gory, but little else. The new co-main event, Josh Koscheck versus Anthony “Rumble” Johnson, may end up being a very entertaining match though neither name will draw any but the UFC faithful. UFC 106 could end up being a pretty good event, but not the highest grossing.
This also happens to be a year when UFC events are crushing other sporting pay-per-views. (The exception to that rule was UFC 103, one of the weakest UFC cards. It did not manage to accumulate more buys than the Floyd Mayweather Jr.-Juan Manuel Marquez fight that occurred the same night.)
UFC 106 will occur on the same night Manny Pacquiao fights Miguel Angel Cotto. There is a strong likelihood that UFC 106 will struggle as UFC 103 did. It'll be a successful pay-per-view instead of one that is enormously successful. (We should all struggle like that.)
The UFC's biggest advantage is that it has a stable of champions and contenders that no one else can match.
Brock Lesnar is just one of several dominant champions like Anderson Silva, Lyoto Machida, Georges St. Pierre and BJ Penn. In fact, Lesnar is the only champion in the UFC that isn't ranked as the world's top fighter in his weight class.
Where else is an MMA fan going to go?