If his MMA career ever got to the point where he felt that he did not possess the ability to be Champion anymore, he would likely finish up any remaining fights on his contract and come back to WWE part-time. I doubt he would ever do any sort of touring schedule or anything, but maybe something along the lines of HBK's late-'00s deal or Triple H's current level of in-ring activity.
Lesnar vs. Cena would be huge if they re-introduced Brock properly to the new generation of fans.
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Thank you, Eddie Guerrero.
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