On October 26, 2009, it was announced that Lesnar had pulled out of the UFC 106 card in which he was set to face Shane Carwin for the UFC Heavyweight Championship due to an illness. UFC President Dana White said that Brock had been ill for three weeks and claimed he had never been this sick in his life and that it would take him a while to recover, his fight with Carwin was rescheduled for UFC 108 in early 2010. On November 4, it was confirmed that Lesnar was suffering from mononucleosis and that his bout with Carwin would have to wait a bit longer, thus the fight for UFC 108 was canceled. On November 14 at the UFC 105 post-fight conference, Dana stated, "He's not well and he's not going to be getting well anytime soon." and that an interim title match might need to be set up. In addition to mononucleosis, it was revealed that Lesnar was suffering from a serious case of diverticulitis, an intestinal disorder, which would require surgery. After further diagnosis, on November 16 Lesnar underwent surgery to close a perforation in his intestine that had been leaking ????? matter into his abdomen, causing pain, abscesses, and overtaxing his immune system to the point that he contracted mononucleosis. From the level of damage to Lesnar's system, the surgeon estimated that the intestinal condition had been ongoing for around a year. Lesnar's trainer stated he has been recovering and will resume training within 6 months.
