Sugar Ray Robinson Ali George Foreman Sugar Ray Leonard Tommy Hearns Marciano Larry Holmes Milton McCrory Evander Holyfield Antonio Tarver
Abraham comes to mind right away. Mosley used to. hmmm PAc carries it pretty well late. Vasquez used to. Froch as well.
What you're saying is who could fight through and get his second wind the better. The power always remains, It's just effected by fatigue and losing technique. it's just some fighters can fight even harder when they get tired. The high octane fighters like Duran, Fenech, Pryor, Chavez etc have to be favoured here. As they had insane ability to maintain intensity even when fatigued. 15 round fighters that had the ability to keep their technique together late are also impressive. James Toney, Ray Leonard, Arguello, Carlos Zarate, Monzon etc are good mentions in that department.