Wrong goal overturned -- that's sport (6)
I believe the answer is:
tennis
'sport' is the definition.
(tennis is a kind of sport)
'wrong goal overturned' is the wordplay.
'wrong' becomes 'sin' (I've seen this before).
'goal' becomes 'net' (net is a kind of goal).
'overturned' says the letters should be written backwards.
'sin'+'net'='sinnet'
'sinnet' written backwards gives 'TENNIS'.
'that's' acts as a link.
(Other definitions for tennis that I've seen before include "Table -, - elbow" , "Wimbledon sport" , "Sport on a court" , "Game played with racquets" , "Court-based sport" .)