Self-inflicted damage to have end (3,4)
I believe the answer is:
own goal
'self-inflicted damage' is the definition.
(goal scored against one's own team)
'have end' is the wordplay.
'have' becomes 'own' (to have something is to own it).
'end' becomes 'goal' (end can mean one's purpose or goal).
'own'+'goal'='OWN GOAL'
'to' is the link.
(Other definitions for own goal that I've seen before include "Disadvantageous move for the party making it" , "A score against one's self or team" , "aids the opposition" , "big mistake" , "Self-inflicted setback" .)