Fielder supports insolence (3,4)
I believe the answer is:
leg slip
'fielder' is the definition.
(I've seen this before)
'supports insolence' is the wordplay.
'supports' becomes 'legs' (leg is a kind of support).
'insolence' becomes 'lip' (I've seen this before).
'legs'+'lip'='LEG SLIP'
(Other definitions for leg slip that I've seen before include "One hoping to hold ball" , "On-side fielder" , "One in the field" , "Position on cricket field" , "Cricketer" .)