Maria Sharapova has announced her retirement from tennis.
The five-time grand slam champion and former world number one has struggled with chronic shoulder problems and has slumped to 373 in the rankings.
In an essay on vanityfair.com, the 32-year-old wrote: "How do you leave behind the only life you've ever known? How do you walk away from the courts you've trained on since you were a little girl, the game that you love – one which brought you untold tears and unspeakable joys – a sport where you found a family, along with fans who rallied behind you for more than 28 years?
"I'm new to this, so please forgive me. Tennis – I'm saying goodbye."
Sharapova will go down as one of the greats of the era – only Serena and Venus Williams have won more slam titles among current players.
But her impact on court was trumped by her profile off it, with the Russian the world's highest-earning female athlete for much of her career.
She made herself a global star by winning Wimbledon aged 17 in 2004 and added the US Open title in 2006 and the Australian Open in 2008 before twice lifting the trophy at Roland Garros, in 2012 and 2014.
Then in 2016 came the bombshell announcement that she had failed a doping test for the cardiac drug Meldonium, which had been added to the banned list at the start of that year.
Sharapova was banned for two years, reduced to 15 months on appeal. She returned to action in April 2017 but was unable to reach her previous heights, peaking at a high of 21 in the rankings and reaching just one grand slam quarter-final.
Sharapova was restricted to eight tournaments last year and struck a pessimistic note about her future prospects after losing in the first round of the Australian Open in January.
Sharapova cited last August's US Open, when she lost heavily to Serena Williams in the opening round, as a 'final signal'.
She wrote: "Behind closed doors, 30 minutes before taking the court, I had a procedure to numb my shoulder to get through the match.
"Shoulder injuries are nothing new for me – over time my tendons have frayed like a string. I've had multiple surgeries – once in 2008, another procedure last year – and spent countless months in physical therapy.
"Just stepping onto the court that day felt like a final victory, when of course it should have been merely the first step toward victory. I share this not to garner pity, but to paint my new reality: My body had become a distraction."
Sharapova first picked up a racket at the age of four before moving with her father to the United States to train, not seeing her mother for two years.
"In giving my life to tennis, tennis gave me a life," she said. "I'll miss it every day. I'll miss the training and my daily routine: Waking up at dawn, lacing my left shoe before my right, and closing the court's gate before I hit my first ball of the day.
"I'll miss my team, my coaches. I'll miss the moments sitting with my father on the practice court bench. The handshakes – win or lose – and the athletes, whether they knew it or not, who pushed me to be my best.
"Looking back now, I realise that tennis has been my mountain. My path has been filled with valleys and detours, but the views from its peak were incredible.
"After 28 years and five grand slam titles, though, I'm ready to scale another mountain – to compete on a different type of terrain."