Dana White today called an unexpected media call to announce that former UFC heavyweight champion Brock Lesnar has fallen ill again with Diverticulitis.

As a result Lesnar will no longer be able to fight Junior Dos Santos in the headline bout at UFC 131 next month which was set to establish the next No.1 contender to face current champion Cain Velasquez.

In his place steps Shane Carwin who will now fight Dos Santos for the chance at a title shot.

Lesnar appeared on the conference call and revealed that the symptoms of the Diverticulitis illness had returned, with his immune system run down and pains in his stomach.

He also divulged that he had in fact been on antibiotics during his stint as a coach on The Ultimate Fighter, and in his preparations for the fight with JDS. He had kept this secret from the UFC, but after deciding that it was preventing him from training the way he wanted to he finally had to tell them earlier this week.

The former champion spent 14 hours at the Mayo clinic yesterday undergoing a battery of tests, and he now faces a tough decision as to whether he will get surgery to attempt to cure the condition.

According to the 33 year-old the illness is not as bad this time as it was in 2009, but if he doesn’t get surgery then he could face a lifetime of battling with the condition.

Regardless, Lesnar is putting a brave face on the situation and says that this is just a bump in the road, and that he has no plans to retire and intends to fight again.