My opinion is this is the toughest opponent Floyd has faced given the circumstances in the fights with bigger names.
Corrales was a top 10 fighter. Hernandez was a top fighter as well. DLH at 154 was a tough test as well.
castillo. but, de la hoya who many considered to be shot at the time he fought floyd, was his last tough fight. de la hoya's size made floyd passive all nite
Thats not saying much about floyds opponents then. A prime cotto would have been a good fight, the latest cotto is past his best
Depends on what you mean. Are you talking about simply the best or the best at the time he has faced them? Mayweather is fighting Cotto past his prime. The same as he did with JMM, Mosley, and Oscar. Castillo was never as good of an all-around fighter as any of them, but was still young and on his way to a great career; not fading away from one.
At no time would Cotto be the best fighter Floyd fought unless we are talking at 140. As it stands today, Cotto is the worst fighter Floyd has fought since the Floyd-Manny BS started. Manny picked the better fighter this time, Floyd can't sell this ****.