As late as 1986 , he proved that he was still the best amateur boxer by winning the world championship at the age of 36 .
By defeating Pyotr Zayev of the USSR in the final , Stevenson earned his third gold medal .
As late as 1986 , Stevenson proved that Stevenson was still the best amateur boxer by winning the world championship at the age of 36 .
By defeating Pyotr Zayev of the USSR in the final , Stevenson earned his third gold medal .