Result of a failure to score: cocaine added to a kilo (kg), roughly (4,4)
I believe the answer is:
goal kick
'result of a failure to score' is the definition.
(type of free kick given in football)
'cocaine added to a kilo kg roughly' is the wordplay.
'cocaine' becomes 'C' (drugs abbreviation).
'added to' is a charade indicator (letters next to each other).
'roughly' indicates anagramming the letters.
'a'+'kilo'+'kg'='akilokg'
'c' after 'akilokg' is 'akilokgc'.
'akilokgc' is an anagram of 'GOAL-KICK'.
(Other definitions for goal kick that I've seen before include "attempt at conversion?" , "action on pitch" .)