Indeed Mike Tyson is probably a very poor example of this because even though he is no doubt immensely talented, he also was not only trained by but adopted by

Indeed Mike Tyson is probably a very poor example of this because even though he is no doubt immensely talented, he also was not only trained by but adopted by Cus D'amato, a very famous boxing coach who dedicated those final years of his life to making sure Tyson became a world champion.