The 2013 Wimbledon champion announced this week she plans to come out of retirement more than four years after playing her last tournament.
Bartoli shocked the tennis world by calling it a day little over a month after winning her first grand slam title at the All England Club, saying her body could not take any more.
She resolutely insisted she would not change her mind but a health crisis in the summer of 2016 made the Frenchwoman think again.
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Bartoli lost a huge amount of weight after picking up a mystery illness and, after returning to full health, has a new desire to get back on the court.
The 33-year-old said at a press conference reported by L'Equipe: "The stopping of my first career in 2013 was heartbreaking as I finally felt I had mastered everything to win these big tournaments, realise my dreams.
"I unfortunately had to stop for a fairly severe injury to my right shoulder, which prevented me from continuing to play at the highest level. It was very difficult to accept as everything stopped suddenly when I still had many goals to achieve.
"If what happened to me in 2016 did not happen, I do not think I would have had this feeling as powerful to want to come back on the courts.
"The genesis comes from the most difficult day of my life, when Wimbledon decided not to allow me to play the legends tournament because they thought I could have a cardiac arrest on the court and die.
"From that moment, I swore that if one day I was healthy again, I wanted to try to relive what I had been lucky enough to live three years before, when I had won the tournament.
"What saved me at that time was tennis, to hang on to the great moments that I lived on a court. That's what kept me alive. That was the starting point of my reasoning, to tell me that I was going to finish what I could not finish in 2013."
Marion Bartoli of France celebrates winning Wimbledon (Reuters)
Image credit: Eurosport
Bartoli, who has turned her hand to TV punditry and fashion design during her retirement, has set a target of the Miami Open in March for her return, and is happy with the progress she has made so far.
She said: "On the tennis level, I'm (at) 80-90 per cent of my Wimbledon 2013 level. Physically, I think I'm missing 40 per cent of this level. It's not a lot, and at the same time a lot of work."
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