Game's left-winger to make complaint (3,6)
I believe the answer is:
red grouse
'game's' is the definition.
(I've seen this before)
'left-winger to make complaint' is the wordplay.
'left-winger' becomes 'red' (red is a kind of left-winger).
'to make complaint' becomes 'grouse'.
'red'+'grouse'='RED GROUSE'
(Other definitions for red grouse that I've seen before include "Game bird" , "Moorland bird" .)