I'll name a fighter, and tell you which match (in my opinion) was their absoloute peak, and give you my reason(s) why----then the next poster must do the same thing, ok?
Fighter: Muhammad Ali
Prime Fight: Kayo 3rd over Brian London
Why: Though many claim Ali's one sided annihilation of Cleveland Williams was his peak, still there is a nagging minority who say Williams was no longer the man he was at heavyweight---however, Brian London, British champ and perrenial heavyweight contender, was just solid enough and near his best, before taking on Muhammad Ali. He went the full route with Patterson just a few years before---he had no excuses---and neither did Ali for his amazing performance.