Many folks watching sports have no CLUE about what's going on in the ARENA down below them.
Sometimes, I find myself among them, not being a fan of professional football because I only went to school games when a grandchild was playing. And while half the Syracuse University football team was in my dorm in college in the days of my youth, I attended one game in the years I was there. The huge crowds, screaming fans, great half-time shows, victories for our side, bloody defeats of our enemies, and the last days of Jim Brown's career and many others who went on to great public fame; all of which as a classicist, I was reminded of ancient Rome, except that the lush lawn (or muddy mess more often) should not be called an "arena"!
The worst part was often finding our way out through the labyrinth under the stands; a true maze in those days, with few signs to guide us, but then, for once, grateful for the crowd to hustle us along, willing or not. You see, arena is a Latin word implying the absorption of quantities of "sand".
Sand was spread in the coliseum at Rome, because it provided a surface that would soak up blood quickly, and could be raked out making all traces of the horrors just occurring there vanish. Fans in those days had an even tougher time finding their way out, because there were no "exit" signs.
I often wondered if anyone ever considered following Perseus example when entering the Labyrinth to slay the Minotaur? He was advised to take a large ball of twine and let it out behind him as he entered so he could find his way out. And the ancient word for twine or string? You guessed it, "clue"!
So it is that both words, "arena" and "clue", have changed their meanings according to how they came to be used: arena is now "any place where a sport takes place"; and clue is any hint as to where some thing or "a piece of information is hidden".
I'll bet you never held up your hands to have your Granny wind yarn into a ball to make a "clue".