List sent in to organise sport (5,6)
I believe the answer is:
table tennis
'sport' is the definition.
(I've seen this before)
'list sent in to organise' is the wordplay.
'list' becomes 'table' (I've seen this before).
'to organise' indicates anagramming the letters (I've seen 'organising' mean this).
'sent'+'in'='sentin'
'sentin' is an anagram of 'tennis'.
'table'+'tennis'='TABLE-TENNIS'
(Other definitions for table tennis that I've seen before include "sport" , "Indoor game" , "Ping pong" , "Ping-pong" .)