Difficult to say to be honest because Roy was such an oddity in so many senses. In Roy's prime there was no style to beat him because he was just a dominant athlete. Roy seemed to do a lot of things on the fly when in the ring so to pinpoint a style to defeat him is almost impossible, sure Nunn was a tall southpaw just like Tarver so the comparisons will imminently flow but Roy just got caught with a hellacious shot. It's not like he was outboxed andsystematically broken down so my answer is that I have no clue but I will say this.....Nunn was no slouch!!!!