Grasp the nettle (4,3,6)
I believe the answer is:
bite the bullet
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">grasp the nettle</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 bite the bullet that I've seen before include "resign oneself?" , "Grapple with a problem head on" , "Commit oneself" , "Be stoical" , "Face the music" .)