A club oddly needing workers to show discernment (6)
I believe the answer is:
acumen
'discernment' is the definition.
(thesaurus)
'a club oddly needing workers' is the wordplay.
'oddly' indicates alternate letters.
'needing' is a charade indicator (letters next to each other).
'workers' becomes 'men' (man is a kind of worker).
The alternate letters of 'club' are 'cu'.
'a'+'cu'+'men'='ACUMEN'
'to show' acts as a link.
(Other definitions for acumen that I've seen before include "Sharpness, penetration, quickness of perception" , "Cleverness in business" , "Wit" , "perspicacity" , "Sharpness of mind, good for business" .)