"Beaten down" by past defeats in Grand Slam finals, Simona Halep "avenged herself" by winning the French Open and will never have to doubt herself again, her psychologist Alexis Castorri has said in an exclusive interview with wtatennis.com. With Halep's breakthrough amid the white heat and "excruciating pressures" of Paris, the World No.1 showed she has "a mighty personality". 

For the last two years, Halep has been working with Castorri, a Florida-based psychologist whose clients have included Andy Murray, Ivan Lendl and another Grand Slam champion who would prefer not to publicise their working relationship. According to Castorri, the Romanian demonstrated great perseverance by defeating Sloane Stephens at Roland Garros to land her first Slam, having lost her previous three appearances in major finals, at the 2014 and 2017 French Opens and this January's Australian Open. 

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"The thing that I'm proudest of with Simona is the snapshot of last year's match [the French Open final, which she lost to Jelena Ostapenko] and what she did this year. I'm just proud of the hard work that she did in those 12 months, internally and within herself. Therefore job well done, period. She will never have to doubt again whether she can do it. She earned that the good old-fashioned way, being beaten down first and then coming back and avenging herself," said Castorri. 

No one has a better insight than Castorri into the mental agonies of losing a bunch of Grand Slam finals. Both Lendl and Murray lost four Grand Slam finals before making their breakthroughs. "These are people who have had multiple tries before they have actually made it. These are people who persevere," said Castorri, who was introduced to Halep by her Australian coach Darren Cahill. 

"You have to be a mighty personality to have victory stolen from you, or for you to lose it yourself, and then to come back the next year, or two years later, and continue to work your way up the mountain. That takes a special kind of perseverance." 

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Castorri spoke of the "excruciating pressure" on tennis players in major finals.

"I don't see any difference in pressure [between Lendl's day and today]. The environment is different but the internal pressure is the same. Winning is winning and losing is losing. The pressures inside a tennis player are the same. As a tennis player, you have to find the best of yourself under excruciating pressure. That has been the constant throughout the ages."  

Simona Halep lifts the trophy (Jimmie48/WTA)

While Halep visited Castorri's Florida home earlier this year, the great majority of their conversations are on the phone. "With my clients, we speak whenever the player feels like it. There's no format. It's just whenever the player feels like they would like a chat. It's different for everybody," Castorri said. 

Speaking in Paris after the French Open final, Cahill has said how Castorri has helped Halep to cope with the stress of professional tennis.

"Dealing with those pressures is really important and Simona has been able to do that. Alexis, in Florida, has been really important the last couple of years. Once upon a time, in my era, maybe admitting to that was a bit of a weakness; you had to suck it up and be tough. But I think players today are turning over every stone and making sure, if they need to do it, they're doing it," Cahill said.  

Even before Castorri met Halep, she admired her - and over the last couple of years, her admiration for her client has only grown.

"I'm extremely proud of Simona," said Castorri. "I admired her before I was introduced to her by Darren. I like passionate people and most of the elite players are passionate. I love Simona's passion and her drive. I admire her work ethic. She's an extremely honest person. She's also very coachable."