You can tell how Aryna Sabalenka is feeling with just one glance.
A missed shot is greeted by gritted teeth, an eye-roll, a choice word towards her coaching team. Winners and aces bring a huge roar to the heavens, clenched fist raised high.
Her emotions fuel her - but they can also hinder her. Nowhere was that more obvious than the French Open final. Seventy unforced errors flew from Sabalenka's racquet as she was outsmarted by Coco Gauff on a windy Paris evening.
She broke down afterwards, apologising for "the worst final I ever played".