Well, Dionisio Miranda has been knocked out 13 times in his 16 defeats. Arias won a majority decision against Miranda not even 2 years ago. Other familiar names on Arias's resume include Scott Sigmon and Darryl Cunningham. This is a massive step up and I don't like his chances.
You say super confident, I'd say he looks super nervous at any sort of faceoff. His body language betrays him. Too much fidgeting and jittery movement.