As you can see, it’s completely bogus. Brock is throwing hooks to the head, Mir moves his head while Brock is throwing and one hits the back of Mir’s head. Brock immediately adjusts and starts throwing hammerfists. The first one is perfectly fine, but then, mid-throw AGAIN, Mir moves his head and one hits the back of the head. Lesnar, instead of pounding away, waits for a second, and Mir thinks he’s about to throw hooks and moves his head, and then Lesnar throws a hammerfist that lands legally on the side of Mir’s head. So, two illegal strikes that were caused by Mir.
Meanwhile, earlier that very same night, that very same referee watched Gleison Tibau repeatedly hit Tyson Grifin in the back of the head and warned him several times with no point deduction, and more importantly, no stand up. Without that stand-up by the incomprehensible Steve Mazzagatti, Lesnar wins via TKO.