A silence follows golf injury (4)
I believe the answer is:
gash
'injury' is the definition.
(gash is a kind of injury)
'a silence follows golf' is the wordplay.
'silence' becomes 'sh' (I've seen this in other clues).
'follows' says to put letters next to each other.
'golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'a'+'sh'='ash'
'ash' put after 'g' is 'GASH'.
(Other definitions for gash that I've seen before include "score heavily" , "Jagged cut" , "extra" , "Deep, jagged tear" , "Open wound" .)