(Reuters) - Reaction in the tennis and sports world to Andy Murray's announcement on Friday that this year's Australian Open could be the British former world number one's last professional tournament:
FORMER WORLD NUMBER ONE BILLIE JEAN KING
"@andy_murray You are a champion on and off the court. So sorry you cannot retire on your own terms, but remember to look to the future.
"Your greatest impact on the world may be yet to come. Your voice for equality will inspire future generations. Much love to you & your family."
FORMER U.S. OPEN CHAMPION JUAN MARTIN DEL POTRO
"Andy, just watched your conference. Please don't stop trying. Keep fighting. I can imagine your pain and sadness. I hope you can overcome this.
"You deserve to retire on your own terms, whenever that happens. We love you @andy_murray and we want to see you happy and doing well."
WORLD NUMBER 51 NICK KYRGIOS
"You will always be someone that impacted the sport in so many different ways, I know this was never the way you wanted to go out, but hey it was a heck of a ride.
"You took me under your wing as soon as I got on tour, and to this day you have been someone I literally just look forward to seeing. You're one crazy tennis player, miles better than me.
"I just want you to know that today isn't only a sad day for you and your team, it's a sad day for the sport and for everyone you've had an impact on."
BRITISH NUMBER ONE KYLE EDMUND
"For me he's been my biggest role model out of any tennis player. He's Britain's greatest tennis player ever and you could say maybe Britain's best sportsman ever."
DOUBLES GREAT BOB BRYAN
"We'll all forever remember the mark he left on our sport... but I'll also never forget the afternoon he carved out of his busy training schedule to help raise money for our kids foundation. This guy has a heart of gold and will always be a legend in tennis and life."
MURRAY'S FORMER COACH DARREN CAHILL
"When you search for examples of 'emptied the bucket to be as good as they could be' there should be a picture of Andy Murray sitting under that quote.
"Remarkable discipline for training, competition, sacrifice, perfection, a little crazy but a legend of a bloke. Bravo Andy."
MURRAY'S FORMER COACH DANIEL VALLVERDU IN RESPONSE TO CAHILL
"Whatever you think 'emptying the bucket' means... times that by 5 and that's who @andy_murray is. Thank you Andy - thank you for always being you. #1"
FORMER U.S. OPEN CHAMPION ANDY RODDICK
"If this is true, I tip my cap to @andy_murray! Absolute legend. Short list of best tacticians in history. Unreal results in a brutal era... Nothing but respect here. I hope he can finish strong and healthy.
FORMER WORLD NUMBER TWO MAGNUS NORMAN
"If true. Feel down to the bone for Andy Murray right now. Amazing player, fighter, nr 1 and multiple GS champion. Deepest respect."
FORMER GRAND SLAM DOUBLES CHAMPION PAM SHRIVER
"A male leadership voice that stands out and is outstanding during a challenging time for gender issues. Andy was able to reach #1 during the Federer Nadal Djokovic era making it the era of the big 4. My family is sending Andy all the love and support from Los Angeles. @JudyMurray"
FORMER WORLD NUMBER ONE KIM CLIJSTERS
"My heart breaks listening to @andy_murray during his press conference... Hope he will make it through to Wimbledon and have the farewell he deserves. #greatguy."
WORLD NUMBER SIX KEVIN ANDERSON
"My thoughts are with @andy_murray and I really hope we continue to see you fighting on court so you can retire on your own terms. Get well soon... Tennis is better with you."
U.S. DAVIS CUP TEAM CAPTAIN MARDY FISH
"The @andy_murray that I know will absolutely make it to Wimbledon to play his final tournament. Not many with more heart, effort in the history of the game. Was always a pleasure to share the court pal."
WORLD NUMBER 38 JOHN MILLMAN
"Andy will always be a titan of our sport. A hero of mine throughout my career. A true warrior whenever he steps on the court."
FORMER U.S. OPEN CHAMPION SAMANTHA STOSUR
"He's been a fantastic player, champion. I mean, he's been a massive advocate for women's tennis and women's sport in general. I know in the locker room whenever we hear him kinda stick up for us, we're like, 'Yeah, go Andy!'"
RUSSIAN PLAYER KAREN KHACHANOV
"Really sad to hear that @andy_murray. You are a true champion of our sport and great example for all of us! Stay strong."
AUSTRALIAN PLAYER THANASI KOKKINAKIS
"You're the man muzz."
WORLD NUMBER 21 GRIGOR DIMITROV
"Tennis will come to an end for us all but the friendships will last a lifetime. What you've done for the sport will live on forever. I'm hoping for a strong and healthy finish for you, my friend! @andy_murray."
"So sad for @andy_murray. Hands down one of the best guys on tour. So much respect for him as an all around athlete and person. Hope his body can recover. If not, he will be missed by all."
SCOTTISH SNOOKER GREAT STEPHEN HENDRY
"Hard to read that @andy_murray being forced to retire because of injury, no doubt one of Scotland's greatest ever sportsmen."
DALLAS MAVERICKS FORWARD DIRK NOWITZKI
GOLF WORLD NUMBER ONE JUSTIN ROSE
"What a career @andy_murray keep it going as everybody wants to watch you @Wimbledon in July mate. #GOAT."
(Compiled by Shrivathsa Sridhar in Bengaluru; Editing by Greg Stutchbury/John O'Brien)