Fine leg spinner, balding (4,2,3)
I believe the answer is:
thin on top
'balding' is the definition.
(I've seen this before)
'fine leg spinner' is the wordplay.
'fine' becomes 'thin' (similar in meaning).
'leg' becomes 'on' (cricket term, fielding positions).
'spinner' becomes 'top' (a spinning top).
'thin'+'on'+'top'='THIN ON TOP'
(Other definitions for thin on top that I've seen before include "with less than full head" , "Balding (colloq.)" , "showing scalp?" , "State of advancing baldness" , "developing a shine for the Head?" .)