One of my friends helped Sun Jun on a China tour of England. Sun Jun was still a junior but had many blisters on his feet which my friend helped treat.
I also saw Sun Jun's last match in the All China games. He got to the semifinals of the doubles and won the mixed doubles. That was only a few months after the Olympics and a complete switch from singles to doubles. An absolute privilege to have seen that.
Sorry to have gone off topic.
Enjoy your snippet of information on Sun Jun and your insight of his game. Originally I know very little about Sun Jun but now I am interested to know more esp after reading of LYB enlisting his help to train and prepare Chen Long for the WC which has borne fruit abundantly.