Many a tournament (4)
I believe the answer is:
open
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">many a tournament</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for open that I've seen before include "hardly high-security" , "still in debate" , "Sports contest" , "with no clear favourite" , "Without concealment" .)