He had to do what he had to do.
His body has been ravaged with injury for years, due mostly to his style of physical play and some just to the nature of the game he played.
I believe him for exactly what he said. The pain, and wear and tear on his body, the never ending rehabs, just drained the joy of the game from him.
He's young, smart, educated, and the game has made him a wealthy young man. All good things come to an end. And for someone like him, after he grieves and he allows his body the time to heal, opportunities will abound.