#2 Brock Lesnar does not want to risk injury
Brock Lesnar is not getting any younger.
He is currently 41 years of age. After a certain age, it becomes difficult for any athlete to lose weight and train as easily as they once were able to do. At this stage, Lesnar might want to take things easier on himself.
Also, one of the issues with UFC is that no matter how good you are, you're not guaranteed a victory. The moment you step into the Octagon with another fighter, you are putting yourself at risk of injuries.
Lesnar has had his share of injuries over the years, and if he enters the Octagon with a fighter as skilled as Daniel Cormier, he is almost certainly ensuring that he will need to put in an immense effort to get a chance at winning anything.
At this point, it might be better for him to concentrate on not suffering an injury.
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