How does secret service ensure trumps safety when he goes to UFC fights?

Typically when you see him anywhere he’s surrounded by Secret Service but when he goes to the UFC fights, they’re seen walking in with him but never seem to be sitting with him when the cameras show him sitting octagon-side. I know typically before presidents go anywhere they check everything to make sure they’re safe but that seems like a logistical nightmare, if not outright impossible for some of the venues UFC events take place at.