Competition's not close (4)
I believe the answer is:
open
I believe this clue is a double definition.
'competition's' is the first definition.
(open is a kind of competition)
'not close' is the second definition.
('open' is the opposite to 'close')
(Other definitions for open that I've seen before include "ready to entertain new ideas" , "Allowing access" , "golf contest" , "gaping" , "'Frank, not secret (4)'" .)