Andy Murray: Billie Jean King leads tributes to Briton who plans to retire this year

Andy Murray has been "a champion on and off court", said American tennis legend Billie Jean King after the Briton revealed he plans to retire this year.

Murray, who has won three Grand Slams and been a world number one, is being forced to quit because of a hip injury.

And the 31-year-old Scot says next week's Australian Open could be the final tournament of his career.

"So sorry you cannot retire on your own terms," tweeted 12-time Grand Slam winner King.

King was one of many former and current players joining fans in offering their best wishes to Murray following his announcement in Melbourne on Friday.

The two-time Olympic champion says he continues to be in "serious pain" as tries to return to the sport following surgery on his right hip a year ago.

He says he wants to play Wimbledon this summer before retiring, but admits that might not be possible.

Kyle Edmund, Murray's replacement as British men's number one, said his compatriot "may be Britain's greatest ever sportsman".

"For me he's been my biggest role model out of any tennis player," said Edmund, who first met Murray when he was 14 and started hitting with him a few years later.

"To be able to have had the experiences that I've had with him and memories of training with him and getting to know him personally, and seeing what he's done on the court and achieved, he's definitely helped my career."

British women's number one Johanna Konta said she could "not imagine the sport without him", while Heather Watson said he "can't be replaced" in British tennis.

"Unable to retire on his own terms and forced to retire is something which no athlete wants to be put through," Konta said.

"Everyone will have a lot of compassion and a lot of sadness for him if he has been put into that position."

Several other players, including close friend Nick Kyrgios and Wimbledon finalist Kevin Anderson, also spoke of their admiration for Murray.

But it is not only Murray's playing achievements that have attracted the praise of his peers.

He has long been a voice for gender equality, often speaking up for players from the women's tour, and in 2014 became one of the first male players to have a female coach when he appointed Amelie Mauresmo.

King, 75, is one of the most influential people in tennis, having fought for gender equality throughout her career and founded the Women's Tennis Association (WTA), as well as being considered as one of the sport's greatest players.

"Your greatest impact on the world may be yet to come. Your voice for equality will inspire future generations," she told Murray in a tweet.

Konta says female players have been grateful for Murray's support.

"There have been many examples of when he has stood up for women's tennis and women in general," she said.

"He has voiced his opinions and has tackled some questions and issues that have arisen.

"I think everybody has always been very appreciative of him and how he has stood up for the women's side of the game."

You have been reacting to the news using #bbctennis. Here's a selection of your thoughts:

Lee Matsell: So sad seeing that Andy Murray press conference. I've followed his whole career and cried with him more than once! Will never forget the gold in London and his first Wimbledon title. What a great man he is.

Paul Hardy: Very sad to hear this, although the writing has been on the wall for a year and half now. Whatever ever happens from now he will be known as one of the British greats.

Pamela Dobbie: Well, wasn't expecting to wake up to this news but I can't say I'm surprised. Andy needs to think of himself and his quality of life now. Thanks for the highlights my boy.

Jo Baines: #bbctennis wants our favourite memories and I honestly can't choose, but his comments about sexism in sport were so vital and unforgettable.

Catherine Imrie: I finally saw Andy Murray at Queens this year after trying for years and that passion, fight and love for tennis is just a few reasons why I love him. He brought me and my family amazing memories and whatever he decides I support him.