Winning appropriate post (7)
I believe the answer is:
upright
'post' is the definition.
(I've seen this before)
'winning appropriate' is the wordplay.
'winning' becomes 'up' (I've seen this in other clues).
'appropriate' becomes 'right' (similar in meaning).
'up'+'right'='UPRIGHT'
(Other definitions for upright that I've seen before include "Vertical, erect" , "Erect - honest" , "Virtuous" , "support" , "Standing straight up" .)