Score with little time left before close of play (6)
I believe the answer is:
twenty
'score' is the definition.
('twenty' can be a synonym of 'score')
'with little time left before close of play' is the wordplay.
'with' means one lot of letters go next to another.
'little time' becomes 't' (abbreviation for time).
'left' becomes 'went' (I've seen this before).
'before close of play' becomes 'y' (I've seen this in other clues).
't'+'went' is 'twent'.
'twent'+'y'='TWENTY'
(Other definitions for twenty that I've seen before include "John B Keane wrote about many young men of this age" , "Dozen plus eight" , "made by Q on a light blue square" , "No. between 5 and 1 on dartboard" , "Number" .)