When it was announced at UFC 199 that former heavyweight champion Brock Lesnar would return after a 4 1/2-year hiatus at UFC 200, the world was abuzz.
Lesnar became the undisputed kingpin of MMA in 2009 when he battered Frank Mir at UFC 100 to avenge his only loss to that point. Before that, he won the heavyweight title by battering Randy Couture at UFC 91. He had taken over the UFC after a leaving a lucrative career in WWE.
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Later, he nearly died in a hospital bed in North Dakota while battling diverticulitis.