Light competition? (5)
I believe this clue is a double definition.
'light' is the first definition.
(I know that match is a type of light)
'competition?' is the second definition.
(I know that match is a type of competition)
(Other definitions for match that I've seen before include "of little use when floodlights fail?" , "Lighter; contest" , "one's struck" , "Striker < in suit" , "Sporting event" .)