Wozniacki's marathon debut was amazing, Djokovic says

LONDON — With the top men's tennis players finishing their own marathon of a season at the ATP World Tour Finals beginning Sunday, there was some talk of the 26.2-mile race that Caroline Wozniacki completed just a week ago in New York.

"I think it was a great idea," world No. 1 Novak Djokovic told reporters inside the O2 Arena Friday. "She wanted to do something for herself that she had never done before. Running a marathon is definitely an amazing experience."

Wozniacki wowed her fans with an impressive 3-hour, 26-minute time, good enough to qualify her for next spring's elite Boston Marathon. She was greeted by pal Serena Williams at the finish line and said it was "the hardest thing" she had ever done.

"We [both live in Monaco] and we're friends and every time I go to practice there I see her running," Djokovic explained, laughing. "She's jogging all the time. She had it in the back of her mind while she was running that she was going to do it, so it's an amazing effort."

Would the top-ranked men's player consider running a marathon himself?

"I do want to run [a marathon] one day. I don't know which city, but I think it will be after my career is over," he said.

Djokjovic isn't alone. In August, Andy Murray told reporters in Cincinnati that he would like to compete in a marathon one day, as well. But to be clear: after his career.

"I will definitely do a marathon at some stage, but not when I'm playing," said Murray, who kicks off tournament play Sunday in London against Kei Nishikori. "It's an amazing effort she's doing that while she's playing because it takes a lot of training, a lot of hard work for that."

Last week in Paris, Roger Federer sang a different tune when it came to marathons. Asked if he was fit enough to complete the distance, he had this to say:

"No. That's totally different fitness we're talking about. That's the endurance fitness that a tennis player doesn't need in my opinion because it's continuous running. We run for 10 seconds and then rest for 10 seconds. We always have these breaks, these intervals. Once you keep your pulse up for a long time that's an entirely different fitness we're talking about."

It doesn't sound like Federer will be taking up marathon training after his career, either.

"I don't like endurance. The whole running part for me is so boring."