H is for haircut.
Cutting your own hair is risky at the best of times, when you're away from the tennis court and sitting at home in front of a mirror; it is even more perilous when you are midway through a round-robin match at the WTA Finals. But, at the 2016 tournament, there was the sight of Svetlana Kuznetsova hacking away at her ponytail during a changeover. The hair had been a nuisance, hitting her in the face. "I was struggling. I thought to myself, 'OK, what's more important now, my hair, which I can grow, or the match?' I thought, 'OK, I got to go for it right now'." Kuznetsova would go on to beat Agnieszka Radwanska. (Getty)