Best-of-five set matches take too much out of the leading men’s tennis players, and shave years off their careers, multiple grand slam champion and women’s pioneer Billie Jean King has said.

Men currently play best-of-five sets at the four major events while the three-set format is used in other ATP World Tour tournaments. Women play best-of-three matches in most competitions, including the grand slams.

The long matches and congested schedules are often blamed for injuries to top players, including Rafa Nadal, Roger Federer, Novak Djokovic and Andy Murray in recent years.

“Personally, I don’t want the men playing five sets anymore. I think it takes too much out of them,” King, who founded the Women’s Tennis Association in 1973, told reporters at the launch of the WTA Finals in Singapore.

“Like one time the players played in the Australian Open final. It took six hours. They could hardly walk off the court. I guarantee you that it took a year off their careers.”

King used the 2012 Australian Open final between Novak Djokovic and Rafa Nadal, which lasted five hours and 53 minutes, to reiterate her point that the current format could be too demanding for players.

She said women were willing to play five-set matches but used the entertainment industry to make the point that athletes will get paid the same regardless of the duration of the matches.

“Everyone keeps saying we don’t want to. We’re very willing. All the women are willing to play three or five sets,” King added.

“It doesn’t matter if (the artists) play for one hour or six hours. They get paid the same amount.”

The season-ending WTA Finals is set to take place in Singapore for the last time this year before moving to Shenzhen, China from 2019 through 2028.