Self-inflicted harm (3,4)
I believe the answer is:
own goal
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">self-inflicted harm</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for own goal that I've seen before include "Shooting oneself in the foot" , "move that backfired?" , "Self-inflicted problem" , "A score against self, as by soccer player" , "that gives advantage to opponents" .)