There style is contrasting though, style makes fight as they say, volume puncher in Brandon, but Mark loves to have his power tested someone chin and see if he can knock him out.
He needs to, remember that when he got the belt against Russell, the later is injured and others says that he wouldn't have won that belt if not for that injuries. And so when he fought Vargas to defend his belt the first time, he lost, and it doesn't sit well. So he has to make a statement win here and proved that his win against Russell and having that belt is no fluke and he is for real and deserved that belt. So if ever he wins, he need to get it back from Vargas.