As a BJJ practicioner I have soft spot for good grapplers in MMA. Demian Maia is the perfect example. Maia has won both the Mundials (World championship in BJJ) and the ADCC (the most prestigeous submission wrestling tournament). In grappling he holds victories over elite names such as Ronaldo "Jacare" de Souza, Yushin Okami, Gabriel Gonzaga and Flavio Almeida (brother of Richardo Almeida).
Demian Maia is at the moment 7-0 (5 submissions and 1 KO) in his MMA career and a contender in the UFC middleweight division. Maia made his professional MMA debut in Finland in december 2005 against Lukas Chlewicki and his latest fight was against Ed Herman in UFC April 2008. Maia is scheduled to take on Jason MacDonald at UFC 87 August 9th.
Maia's best quality as a fighter is of course his ground game. He is very technical both on top and from his back. He has excellent positioning skills and that's why he often is able to finish his fights with a choke from the back or an armbar from mount. With Jiu-Jitsu of this caliber he can win many fights, but the higher he goes in the ranking the more he will need to be well rounded. Striking is absolutely essential to be a top contender in MMA today, but in my opinion wrestling should be the first priority for any ground wizard. Wrestling in itself doesn't win many fights, or at least shouldn't, but the ability to control where the fight takes place is invaluable. Too many BJJ experts have lost matches due to the simple fact that they can't get the fight to the ground or by gassing themselves out in the process. Now, I'm sure Maia trains all aspects of MMA and is constantly improving his weaknesses.
The big question you have to ask , when talking about a middleweight contender in the UFC today is of course; Can he beat Anderson Silva? At this moment he doesn't deserve a title shot and would probably get destroyed. On the other hand if he can get up to a handful of fights more before he steps into the octagon with Silva he might have his chance. Maia's upside is his grappling skills. Silva is good on the ground but he has been submitted before. This also ties in to the point I made earlier about wrestling. Maia will never be as good of a striker as Anderson Silva is, but if he can control where the fight takes place, in this case taking it to the ground, the odds will be more favorable.
Here are some of Maia's fights:
Demian Maia vs. Lukas Chlewicki
Demian Maia vs. Ryan Stout
Demian Maia vs. Ronaldo "Jacare" de Souza (BJJ)