I don't even know if Lopez had an aura of invincibility, Gamboa would have showed up with the intent to wreck him either way.

If anything, and I'm not saying Lopez wasn't taking things seriously enough, but even if he slightly was he should know now that there are bad dudes out there that want his belt and are coming to hurt him. He probably knew that anyway but it was definitely a reminder.

Mtagwa-Villa was a FOTY type fight (he was hurt bad in that fight and came back to KO Villa the next round), he is a rough guy and a good example of a fighter that hasn't made the kind of money he wants to make and is determined.