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 of this year.
Baltacha, who was British number one for nearly three years, retired from the sport 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.
Video: Summary of Elena Baltacha's tennis career
Baltacha learned she had liver cancer in mid-January 2014, two months after retiring from professional tennis and only a few weeks after marrying.
"She was an amazing person and she touched so many people with her inspirational spirit, her warmth and her kindness," added Severino.
Baltacha was diagnosed with primary sclerosing cholangitis, a chronic liver condition which compromises the immune system, aged 19.
Despite her illness and 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 11 years.
The current women's British number one Laura Robson took to Twitter to pay tribute to her "team-mate".
She tweeted: "Impossibly sad. Forever a team-mate. Sweet dreams Bally."
Martina Navratilova, who won a record 18 Grand Slam Singles titles, including Wimbledon nine times, said: "Elena Baltacha was a great fighter on the tennis court.
"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.
"Elena was taken from the world much too soon - fighting to the end and we will miss her."
Eighteen-time Grand Slam singles champion Chris Evert tweeted: "Rest in Peace, beautiful Elena Baltacha... No words... Thoughts and prayers..."
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."
Ian 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.
"We have so many special memories to cherish, but this leaves a gaping hole for everybody in both British and women's tennis, and words simply cannot express how saddened we are by this news."
It was eight years after being diagnosed with a chronic
liver condition that Elena Baltacha broke into the
world's top 50.
Her achievements as a player, which included reaching
the last 32 of a Grand Slam on three occasions, were
even more considerable when you appreciate the often
debilitating condition she lived with.
Baltacha also represented Great Britain for 11 years in
the Fed Cup and along with Anne Keothavong showed
Laura Robson and Heather Watson what might be possible.
She only officially retired from playing at the end of last
year, just before marrying her former coach Nino Severino,
who helped her develop the Elena Baltacha Academy in
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, Andy 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.
Queen's Club tournament director and Great Britain Davis Cup player 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."