There are some fights that were possible but they never happened. In the case of Joe Frazier verses Ken Norton a little bit of alternative revisionist history is needed to set the stage for the fight to have happened. The following, of course, is fiction and it is my take on how such a fight may have transpired.
It is May 1974 and former heavyweight champion Joe Frazier is in training to fight fellow highly ranked contender Jerry Quarry who had defeated up and coming contenders Earnie Shavers and Ron Lyle the previous year. Frazier, who was fresh off a loss to fellow ex champion Muhammad Ali, knew a win over Quarry would solidify another heavyweight title shot against the man who had brutally taken his title from him, George Foreman. But as luck would have it Quarry, who was prone to cuts, was cut while training and the injury was severe enough to sideline him for the next couple of months. Frazier was told by several promoters and by representatives of the major sanctioning bodies that he had to beat a top ranked contender in order to be considered for another title shot. But the problem was that if Quarry, who fit the bill, was not available, and both Lyle and Shavers who had already been beaten by Quarry had slipped in the rankings, who was available for Frazier to fight?