Before the Liston Leotis fight, Cossell says "This is the best shape I have seen Liston in, since the hernia bout. The hernia bout is the match that Liston should have fought Ali, where Ali's hernia put off the fight." Liston does look great during the fight. But wow, Martin REALLY impresses me. His head is in the game the entire fight, focusing on distance, movement, and countering Listons jab. Douglas vs Tyson was a great upset, and many may argue it was a tougher feat for Douglas to win, than it was for Martin. However, Martins performance against a dominant Liston to me was much more impressive.
Sonny told Foreman that he had been sick and it just caught up to him and as ThegreatA said he was just gassed out. It was Leotis' career highlight and a great hook but an aged and maybe illing Sonny was heading for the win until then.
