Britain's former world number four Johanna Konta has announced her retirement from professional tennis.
Konta, 30, reached the Wimbledon semi-finals in 2017 - the first British woman to achieve the feat in 39 years.
She also made the last four at the 2016 Australian Open and the 2019 French Open, while her best result at the US Open was a quarter-final run in 2019.
She made the announcement on social media, saying she was "grateful" for the career she had had.
"Through my own resilience and through the guidance of others, I got to live my dreams," she posted. "I got to become what I wanted and said as a child. How incredibly fortunate I count myself to be."
Born to Hungarian parents in Australia before moving to the UK aged 14, Konta switched allegiance in 2012 and went on to become the most successful British female player of her generation.
In an impressive career, Konta earned a number of accomplishments that no other woman from the nation had achieved for more than 30 years.
As well as her Grand Slam performances and ranking among the world's best, she also won four titles on the WTA Tour and represented Britain in the Fed Cup.
Konta's future had been unclear for a little while, having dropped to 113th in the world after struggling for form and fitness.
Since making the quarter-finals for a third successive Grand Slam at the 2019 US Open, where she lost in straight sets to Ukrainian fifth seed Elina Svitolina, Konta has won only one match in five majors.
Her last tour match came at the Cincinnati Open in August, when she lost to Czech Karolina Muchova in the first round.
In the past few seasons she has dealt with tendonitis in her right knee, something she said in June she would have to manage for the rest of her career.
Further disruption to her career has been caused by the coronavirus pandemic.
Because of the tour being stopped in early 2020, and her doubts about travelling once it resumed in August, Konta was only able to play nine tournaments last season.
This year, Konta showed glimpses of her best form when she won the Nottingham Open - leading to hopes she could have another deep run at Wimbledon in July.
But more bad luck came her way. She was ruled out of her home Grand Slam on the eve of the tournament because one of her team tested positive for Covid, then contracted the virus herself and was ruled out of the Olympic Games in Tokyo.
Since then she has only played twice, in Montreal - where she beat third seed Svitolina - and Cincinnati.
She was replaced by Emma Raducanu as British number one on the teenager's way to winning the US Open in September, with Konta dropping out of the world's top 100 last month for the first time since 2015.
'A tremendous inspiration for so many' - reaction
Anne Keothavong, Great Britain's Billie Jean King Cup captain: "What Johanna accomplished on the court was incredible, but her professional aptitude is what set her apart. As a Billie Jean King Cup player representing her country, she laid it all out there, led by example and who can forget her marathon performances in 2019 during our first home ties in more than quarter of a century?"
Iain Bates, LTA head of women's tennis: "Johanna is a tremendous inspiration for so many in British tennis and everyone at the LTA and involved in the sport is immensely proud of what she has achieved... She leaves a legacy of perseverance, determination and professionalism that will be carried forward by the current and next group of players."
Greg Rusedski, former British number one: "Well done on a brilliant tennis career. You should be so proud of everything you have achieved."