Complete justification for narrow escape (5,4)
I believe the answer is:
close call
'narrow escape' is the definition.
(synonyms)
'complete justification' is the wordplay.
'complete' becomes 'close' (I've seen this in another clue).
'justification' becomes 'call' (something unjustified is uncalled for).
'close'+'call'='CLOSE CALL'
'for' is the link.
(Other definitions for close call that I've seen before include "One may be disputed in court" , "Narrow decision" , "Narrow squeak" , "A near thing" , "hang up" .)