Nothing against AFL sides at cricket ground (4)
I believe the answer is:
oval
'cricket ground' is the definition.
(London cricket ground)
'nothing against afl sides' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'against' becomes 'v' (abbreviation for 'versus').
'sides' means to remove the middle letters (only the letters on the sides are used).
'afl' with its middle taken out is 'al'.
'o'+'v'+'al'='OVAL'
'at' is the link.
(Other definitions for oval that I've seen before include "6D 5A [TUBE STATION]" , "Ellipse" , "It's egg-shaped for cricketers" , "not quite round" , "Where England regained the Ashes" .)