The clue is- Retiring player entertaining forward until my operation (13). From the letters I have ??N?I??E???M? the answer seems to be TONSILLECTOMY. Can anyone provide the logic?
Answer is right.
Retiring player is cellist backwards
"on" within the word cellist is entertaining forward, forward meaning "on"
"until my" is "to my"
Hence tonsillectomy. [well, that would be my reasoning]]