Why is a 6 footer clearly not going to win many headers ?
For Wharton's sake I hope he doesn't have the sort of defeatist attitude shown in your post. To reach the very top in any walk of life requires a determination to be the best possible, not just giving up when things seem hard. To quote the old prayer " Do not ask for tasks equal to your powers, ask for powers equal to your task".
A shining example of the right mentality would be Andy Murray where early in his career it looked as if stamina might be an issue; he worked his socks off to be one of the iron men of tennis. There is no reason why Wharton can't do something similar.