The difference between a good player and a champion is stress management, says tennis great Billie Jean King.

Champions are calm in moments of intense pressure. It makes them thrive. They stay on top because they love the idea of being No. 1.

Look at the emotional make-up of Roger Federer and Serena Williams, says King, who won 12 Grand Slam singles titles and 16 Grand Slam doubles titles before her retirement in 1983 at age 40.

“Roger is the guy to beat. He’s still No. 1 in the world. He knows how to win and he thrives on it,” King said at the Australian Open. “The guy loves tennis. He’s passionate about it.”

Some players talk about the burden of being No. 1 and feeling the weight of the tennis world on their shoulders.

“Some players don’t enjoy being No. 1. They don’t like it, so they’re not going to be No. 1 for long,” said King, the American who was ranked No. 1 five times between 1966 and 1974 and was in the top 10 a total of 17 years.

“It’s the person who can enjoy the moment of having pressure, that they actually look forward to it,” said King.

A champion, for example, will not pray for a double fault when facing an opponent’s serve.

“You want to say, ‘Give me your best shot. I want the ball,” King said.

When faced with a speeding ball, champions possess “a sense of alertness but calmness,” King said, that allows them to line up the perfect shot without getting frantic and missing their mark.

On the women’s side, King admires the drive of 11-time Grand Slam singles champion Serena Williams.

“Serena has tremendous will to win, she really does,” King said. “She’s amazing, actually.”

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