Persist in spite of difficulties (7,2)
I believe the answer is:
soldier on
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">persist in spite of difficulties</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for soldier on that I've seen before include "Persevere (colloq.)" , "Doggedly continue" , "... to bear up" , "Keep struggling" , "Don't give up" .)