Lesnar underwent "minor surgery" this past November for intestinal diverticulitis. Lesnar should be visiting the doctor this week, at which time they should be able to determine if Lesnar will require additional surgery.
The full extent of Brock Lesnar's health problems have never been fully disclosed, but the main issue affecting him is intestinal diverticulitis, according to the sources close to the situation.
Lesnar himself has been quiet on the issue. Diverticulitis only usually requires surgery in extremely bad cases.
Symptoms of diverticultis can include intense pain, nausea, fever, constipation, and diarrhea.
In total, there are really two different possibilities that could happen when the doctor meets with Lesnar.
He could be "cleared," and given a timeline for recovery that will likely include a return to a more normal diet, and a return to more intense training.
If Lesnar is able to begin training relatively soon, the UFC will probably avoid creating an interim title match.
Otherwise, if Lesnar has not recovered enough he will be looking at further surgery, and if there are any more complications, it may simply be unreasonable to assume any return to the UFC.
If further surgery is required, it appears that the UFC is considering an interim title fight between Shane Carwin and Frank Mir, with the winner likely facing the winner of the UFC 110 fight between Cain Velasquez and Minotauro Nogueira.
Even if Brock Lesnar does return, some people like Frank Mir have suggested that the Champ may not be able to return to his full strength.
Mir suggested that since the intestines are important in the absorption of protein and nutrients, that any intestinal damage could affect Lesnar's ability to sustain his physique, which is obviously partially responsible for his success, although a great wrestling background an an apparently great ability to learn MMA also has helped.
That being said, I'm not sure if Mir's remarks regarding Lesnar's illness are completely accurate.
Diverticulitis usually affects the large intestine, while the small intestine is responsible for the absorption of protein and many nutrients. I'm no doctor, but from the knowledge available, it is difficult to say if Lesnar's nutrient uptake will be affected.
Typical treatment for diverticulitis does include a change in diet, but not necessarily a decrease in protein intake.
The other thing to consider is that we really don't know the full extent of Lesnar's illness. Diverticulitis may only be part of the problem. Any further problems could explain why Dana White believes that Lesnar's career may be truly in jeopardy.
The consequences of a Lesnar retirement would not be good for the UFC.
He has enormous drawing power, and is one of the most charismatic figures that you'll ever see. His mere presence makes the UFC bigger, stronger, and more valuable.
But not only is Lesnar a big draw, he also surprisingly gives the UFC heavyweight division some added credibility.
Call me crazy, but I think that Lesnar really helps people think that the UFC heavyweights are better than the Strikeforce heavies.
Among the UFC heavyweights, you have a strong group of guys, but still nobody like Fedor.
Nogueira has the second-best record among heavyweights, but he has lost to Fedor decisively on two different occasions, even though the losses weren't quite as one-sided as revisionist historians might have us believe.
Frank Mir has re-invented himself, but has too many unimpressive performances for some people to believe that he is really able to beat the best fighters consistently.
Obviously, severe injuries and a previous lack of training discipline have been factors affecting his performances, but it will take a solid victory over Cain Velasquez to prove that he's really a different fighter.
Cain Velasquez, likewise, is a ways away from proving himself. He's a great fighter, but hasn't yet shown the ability to stop a durable opponent.
Fedor is notoriously hard to stop, so most people think that while Velasquez might be able to do well against Fedor for a while by using his wrestling, that Fedor would still be much more likely to end the fight.
A win over the less-durable Mir isn't going to end questions about him in the mind of the public. Velasquez will likely need to smash someone like Shane Carwin to really convince people of his stopping power.
Carwin is hulking, and seems to have the punching power that Velasquez lacks, but he's also a bit of a plodding striker.
He could take Fedor down, or get lucky with a big punch, but most people seem to think that were he to fight Fedor, he would probably get knocked out.
Let me be clear for a moment, though, to avoid misunderstanding: These four are great heavyweights. Without even considering Lesnar, the UFC might arguably have four of the best five heavyweights in the world, and as many as seven out of the top ten.
Currently, some people have Brett Rogers, Josh Barnett, Fabricio Werdum, Alistair Overeem, and Andrei Arlovski in their top tens.
I don't really know how much longer that will last considering how fast Carwin, Velasquez, and Junior Dos Santos are rising, and how fast the stars of Josh Barnett and Andrei Arlovski appear to be falling out of the public eye.
Brett Rogers, in my opinion really should never have been ranked so high, considering his ranking is based almost entirely upon a win over the glass-jawed Arlovski, and the fact that he lasted more than a minute against Fedor.
Add on to that the fact that Werdum is due to get his face smashed in this April, and we could quickly be seeing a rankings table dominated by the UFC.
But without anybody who the majority of people think can beat Fedor, there is still a problem.
Lesnar is probably the one guy who many people think would stand a really good chance against Fedor.
Some will disagree with me, but I think that a healthy Lesnar could be a nightmare for Fedor.
While Fedor is a good grappler, he has been taken down by wrestlers in the past, including a 43-year-old Mark Coleman.
Fedor's disciples tell me that Fedor doesn't actually get taken down, but rather that he lets people bring the fight to the ground. I tend to disagree vehemently.
For those who further question Lesnar's ability to take Fedor to the ground on the basis of Lesnar's stand-up, there are a few important things to consider.
First of all, Coleman has worse standup than Lesnar, but was still able to take him down multiple times, despite being over 40 years of age.
Secondly, while Lesnar may not be a great standup fighter, he is impressively fast-moving, so he would be able to close distance extremely well if he wanted to take the fight to the ground, and he wouldn't mess around with the stand-up like he did in the second round against Frank Mir.
Once the fight reaches the ground, Lesnar has more than enough punching power to stop the fight either by facial damage, or knockout.
Aside from having the ability to finish Fedor, Lesnar has also become very difficult to submit. He already had great ground control from his wrestling background, but according to various reports from fighters who have rolled and sparred with him, he's picked up the Jiu-Jitsu game very quickly.
If Lesnar can come back from his illness and successfully defend his belt, he's quite simply going to make people forget about Fedor just a little bit.
If that happens, and there is some real confusion as to who is the best heavyweight in the world, then the UFC will have scored a devastating blow against it's new nemesis, Strikeforce.
Obviously, there are going to be a ton of people still backing Fedor as the best fighter in the world, but Lesnar is a fighter many people have come to believe in.
The UFC will still be more than fine if Lesnar is unable to continue, but his value for the UFC cannot be overstated.
By Darren Wong
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