After game, large English fan, say, is a critic of foul play (7-6)
I believe the answer is:
whistle-blower
'is a critic of foul play' is the definition.
I know nothing about this answer so I cannot tell whether this works.
'after game large english fan' is the wordplay.
I cannot really see how this works, but
'game' could be 'whist' (whist is a card game) and 'whist' is found in the answer.
'large' could be 'l' (eg in clothes sizes) and 'l' is present in the answer.
'english' could be 'e' (abbreviation) and 'e' is located in the answer.
'fan' could be 'blower' (blower is a kind of fan) and 'blower' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'say' acts as a link.
Can you help me to learn more?
(Other definitions for whistle-blower that I've seen before include "Person with inside information making public some illicit activity" , "One who informs on malpractice" , "Person revealing improper activities" , "Teller of tales to the authorities - referee?" , "Informer on illicit activities" .)