Former British number one tennis player Elena Baltacha has died of liver cancer, aged 30.
Born in Ukraine and raised in Scotland, Baltacha revealed she had the illness in March.
Baltacha, who was British number one for nearly three years, retired in November 2013.
"We are heartbroken beyond words at the loss of our beautiful, talented and determined Bally," said husband Nino Severino, who was also her coach.
"She was an amazing person and she touched so many people with her inspirational spirit, her warmth and her kindness."
Baltacha learned she had liver cancer in mid-January 2014, two months after retiring from professional tennis and only a few weeks after marrying.
More than 50 players, including British number one Andy Murray, held a minute's silence on the centre court at the Madrid Masters on Monday.
Murray told BBC Sport it was "tough" to understand such a "tragic" loss, and to comprehend how quickly the illness had advanced.
Baltacha, who died in the early hours of Sunday, was diagnosed with primary sclerosing cholangitis, a chronic liver condition which compromises the immune system, when she was 19.
Despite her illness, which she had to control with medication and regular blood tests, and suffering from multiple injury problems, Baltacha went on to reach the Australian Open third round in 2005 and 2010 and reached a career-high world ranking of 49.
She won 11 singles titles, made the third round of Wimbledon in 2002 and was part of Great Britain's Fed Cup team for 12 years, under the captaincy of Judy Murray.
Among a host of tennis stars paying tribute, current women's British number one Laura Robson took to Twitter to say: "Impossibly sad. Forever a team-mate. Sweet dreams Bally."
World number one Serena Williams tweeted: "My deepest prayers, thoughts, concern and love goes out to Elena Baltacha's family. I am deeply sorry for your loss. Revelation 21:4."
Eighteen-time Grand Slam singles champion Martina Navratilova, who was treated for breast cancer in 2010, said Baltacha had been "taken from the world much too soon - fighting to the end and we will miss her".
"We as tennis players always worry about our bodies, trying to keep injuries at bay.
"But cancer - you can't prevent that and you can't rehab it either - and no matter how much of a fighter you are, sometimes cancer wins."
Billie Jean King, six times a Wimbledon singles champion, tweeted: "Saddened to hear about Elena Baltacha's passing. My fondest memory with Bally was sharing a wonderful chat when we met the Queen at Wimbledon."
Baltacha's former coach, ex-British number one Jo Durie, said it had been "very draining and tiring" for Baltacha "because she was battling her liver condition as well as pushing her body to the limits as an athlete".
"I have this image of 'Battling Bally' giving her all on court in every match.
"She didn't want to talk about her illness, but rather talk about her tennis and how that was going. She was such a fighter."
Iain Bates, the Lawn Tennis Association's head of women's tennis, said: "We have lost a shining light from the heart of British tennis - a true role model, a great competitor and a wonderful friend."
Stacey Allaster, chairman and chief executive of the World Tennis Association, added: "Elena's journey was never an easy one and yet she consistently showed her strength, good humour and indomitable spirit."
Baltacha's agent and friend Eleanor Preston told Sky News: "It was part of Bally's emotional make-up to be very stoic. She never once asked 'why me?' or 'why is this happening?' She was incredibly strong and determined and that was who she was.
"She achieved an awful lot - and in the context of having a serious liver condition that she struggled with since the age of 19. This is why she should be held up as a role model.
"She went through it all without the slightest bit of self pity or ego."
A host of stars, including Navratilova, Robson, Murray, Ross Hutchins, Tim Henman, Greg Rusedski, Jamie Murray, Jonny Marray, Anne Keothavong and Heather Watson have agreed to take part in a fundraising event, The Rally Against Cancer - Rally For Bally, which will now be held in her memory on 15 June.
The mixed doubles exhibition matches at the Aegon Championships at Queen's Club, the Aegon Classic in Birmingham and the Aegon International in Eastbourne will raise money for the Royal Marsden national cancer charity and the Elena Baltacha Foundation.
Great Britain Davis Cup player and Queen's Club tournament director Hutchins, who is in remission from Hodgkin's lymphoma, a form of cancer, told BBC Sport: "We all wanted the Rally for Bally to lift Elena, but now this special event will be held in memory of Elena.
"She was a special person who will be remembered for positive things; a hard worker, a true professional and someone who gave so much back to the sport of tennis."
Tributes from across the sporting world
"What sad news to wake up to today. My thoughts and prayers are with Elena's family on their tragic loss." Former world number one Maria Sharapova.
"Very sad to hear that Elena Baltacha has passed away. RIP." Men's world number one Rafa Nadal.
"I have no words to describe my sadness. RIP @ElenaBaltacha." Current Wimbledon champion Marion Bartoli.
"Impossibly sad. Forever a team-mate. Sweet dreams Bally." British number one Laura Robson.
"Such sad news about Elena Baltacha. My thoughts go out to her family and friends." Olympic cyclist Sir Chris Hoy.
"The Club is saddened to learn of the death of Elena Baltacha. Truly inspirational woman, a sad loss. RIP 'Bally'." Ipswich Town football club, where her father Sergei played from 1988-90.
Current world number one Serena Williams: "My deepest prayers, thoughts, concern and love goes out to Elena Baltacha's family. I am deeply sorry for your loss. Revelation 21:4."
"Really sad to hear the news of Elena Baltacha. My thoughts are with her family and friends." World number three Agnieszka Radwanska.
"Sad to hear about Elena Baltacha. She was a true leader for England's tennis players. She always gave 100%." Nick Bollettieri, former coach of Andre Agassi, Jim Courier and Monica Seles.
"Words can't describe... you inspired and humbled everything you touched. I know you're in heaven because that's where angels belong. Rest in peace Bally. You will never be forgotten." British number two Johanna Konta.
"We've lost our lovely Bally, too young. Rest in peace. My thought are with Nino and all of her family xx" British number three Heather Watson.
So sad to hear of Elena Baltacha's passing - my thoughts are with her family and loved ones, gone much much too soon..." Eighteen-time Grand Slam singles winner Martina Navratilova.
"It is tragic that Elena Baltacha died so young and with so much yet to do and give and offer. Thoughts and love to family and friends." Former British number one Andrew Castle.
"Genuinely jolted by the sad news of Elena Baltacha's death, aged just 30. Thank you for your 11 years for GB in the Fed Cup - RIP." Former England rugby international Brian Moore.
"What a sad start to the day as Elena Baltacha loses battle with liver cancer :(" Former rower and four-time Olympic gold medal winner Matthew Pinsent.
"So sad to wake up to the terrible news of Elena passing away! RIP Bally! Thinking about her loved ones..." Former world number one Kim Clijsters.
"Rest in Peace, beautiful Elena Baltacha...No words...Thoughts and prayers..." Eighteen-time Grand Slam singles winner Chris Evert.
"Thoughts of everyone connected to Team GB & British Olympic Association are with the Baltacha family at this time." Team GB.