Jeez this was a long time ago lol, 10th rd I meant. I knew it was the10th rd but quite often my brain just doesn't function properly and I type the wrong thing, guess I fit in here.
In terms of arm punches, it's been a million years since I've seen the fight but I doubt all were arm punches. There was a lot of movement going on and again the pressure from Mayweather, not saying he has tremendous cardio or anything but it is exhausting when somebody pressures you a lot, Conor is used to being the one with the striking advantage and the one who controls the pace of the fight.
I have done a bit of boxing training and even just doing 3 rds of very light sparring with somebody pressuring you is exhausting.