Collection round pub raised for sport (6)
I believe the answer is:
tennis
'sport' is the definition.
(I've seen this before)
'collection round pub raised' is the wordplay.
'collection' becomes 'set' (I've seen this before).
'round' means one lot of letters goes inside another.
'pub' becomes 'inn' (I've seen this before).
'raised' says the letters should be written backwards.
'set' enclosing 'inn' is 'sinnet'.
'sinnet' back-to-front is 'TENNIS'.
'for' is the link.
(Other definitions for tennis that I've seen before include "Sent in strangely to play the game" , "Popular racket game - anyone for it?" , "McEnroe's game" , "event" , "Net sport" .)