What is the single most important quality in a tennis champion? I would have to say desire, staying in there and winning matches when you are not playing that well.
John McEnroeOn a given day, Serena Williams could beat some players. I believe because she's so incredibly strong mentally that she could overcome some situations where players would choke 'cause she's been in it so many times, so many situations at Wimbledon, The U.S. Open, etc. But if she had to just play the circuit - the men's circuit - that would be an entirely different story.
John McEnroe