USA runner goes viral for the size of his UNDERWEAR - before winning his 400m heat at 2024 Paris Olympics

Fans of Olympic running were left surprised by American track star Quincy Hall and his choice of underwear.

Cameras caught Hall putting on his track suit in the belly of the Stade de France before taking part in his heat for the 400m.

Hall was seen putting the suit on - but one user on Twitter was surprised that the runner chose to wear baggier boxers more than a more streamlined option.

'Tell me this isn't the craziest thing you've seen thus far in the Olympics. Quincy Hall with the loose boxers under the track suit,' the user wrote while filming the broadcast, adding, 'No f****in' way he's winning.'

Hall saw the post and quote-tweeted it with the comment, 'Yea way country boy big draws.'

Fans were shocked to see American runner Quincy Hall wearing boxers under his track suit

They didn't slow Hall down - who even watched his race on a screen while he was competing

While funny to some, Hall's choice in undergarments clearly didn't hold him back in the 400 meters.

In fact, Hall was so confident in his result that he was seen watching his heat race while he was competing.

Indeed, Hall won his heat - looking effortless in doing so - with a time of 44.28 getting the job done for him.

Hall was a bronze medal winner at the 2023 World Championships in Budapest and was part of a gold meal winning 4x400m relay team alongside Vernon Norwood, Justin Robinson, and Rai Benjamin.

Earlier this year, Hall set his personal best time in the 400m at Monaco - running a 43.80.

Next up for Hall is the semifinals of the 400m - which takes place at 1:35pm ET tomorrow.