4. Chael Sonnen
Gregory Payan/AP/Press Association ImagesHe's one of the most popular and polarizing fighters ever, been a part of several of the best-selling cards the UFC has promoted, played a key role in the company's top feuds and made himself and his bosses tons of money. But when it comes down to brass tacks, his actions inside the cage aren't a fraction as entertaining as what he does when locked inside of it. When Chael Sonnen returned to the UFC in 2009, he lost his first fight by submission to Demian Maia in the opening round. Never one to give in to adversity, "The American Gangster" knuckled down and ground out three straight decision wins over Dan Miller, Yushin Okami and Nate Marquardt. None of those were pleasant to watch by any stretch, but that landed him a title shot against Anderson Silva, and thus the greatest rivalry in MMA began. No one will argue those two fights weren't thrilling just for the sheer spectacle, but sandwiched in between those were two snoozers with Brian Stann and Michael Bisping, where Sonnen used his superior wrestling to nullify his opponent's attack. The best thing you can say about Chael's fighting technique is that, while it often isn't pretty or even fun to watch, he does engage and go straight toward his opponent, which is more than can be said about some of the men on this list.