Long race (8)
I believe the answer is:
marathon
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">long race</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 marathon that I've seen before include "Race of about 26 miles" , "Roman hat (anag) - race" , "26-mile foot race" , "The longest foot-race" , "Long run (with a wall to get through!)" .)