If you look at a 45 fight career - he has been in with pretty much all of the leading names of the past 20 years. Received the odd gift UD, and been ripped off on a similar number of occasions. Never been close to being stopped by any head shots - the only time was the Hopkins body shot. Against a much bigger guy - and he was right in the fight as well. Not winning it on my card, but competing all the same.
Exellent chin. Has had a few flash knockdowns but his legs were buckled when PBF caught with an accurate right on the chin in the fifth round.
If Pac carries the power up it's very possible, he's quick enough to surprise him. I just can't see it though, I'm thinking he's just to small. You just never know though.