Briefly scrutinise one disturbing Ashes game (4,5)
I believe the answer is:
stud poker
'game' is the definition.
(stud poker is a kind of game)
'briefly scrutinise one disturbing ashes' is the wordplay.
'briefly' means to remove the last letter.
'scrutinise' becomes 'study' (I've seen this before).
'one disturbing ashes' becomes 'poker' (I can't justify this - if you can you should give a lot more credence to this answer).
'study' with its final letter taken away is 'stud'.
'stud'+'poker'='STUD POKER'
Can you help me to learn more?
(Other definitions for stud poker that I've seen before include "Card gambling game -- Turk's dope (anag)" , "Variation of five-card gambling game" , "Gambling game with some cards turned face up" , "It involves dealer" .)