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Mental health issues. Sexuality. Financial worries. Leaving home for the first time. Death.

American player Noah Rubin, the 2014 Wimbledon junior champion seeking to fulfil his promise on the ATP Tour, is giving his fellow professionals a platform to open up - whatever the subject.

His Behind The Racquet project, inspired by Humans of New York - a revealing photoblog of the city's residents now tracked by millions of social media users worldwide, sees current players, former players and celebrity fans including British comedian Miranda Hart pose behind the strings of a racquet.

Accompanying the striking image is an emotive personal story.

"This has never really been done before, something that shows what these people, who are thought of as having perfect lives or doing really well because they are professional players, are really going through," Rubin tells BBC Sport.

"You really get an understanding of what they're going through on a day-to-day basis, what their thought process is, what their mentality is, how they are feeling, how their family is, just how difficult tennis is."

Rubin, 23, is determined to influence change in a sport which he says is "very tough on the body and the mind".

Belgian player Alison van Uytvanck, in a post published earlier this month, gives a candid insight into the low self-esteem she felt as a youngster when she was bullied at training camps because of her ginger hair.

"I never felt so alone, having no friends and unable to really talk to parents," she says. "I had no-one to lean on for help and found myself crying in my room day after day."

Rubin believes a fundamental overhaul of the game is needed to help improve the mental wellbeing of the players, while he also says more support pathways need to be opened up.

Improved access to psychologists and the creation of outreach programmes for youngsters, where a former professional is easily contactable to offer advice, is a key strategy outlined by Rubin.

"The seasons are way too long, the matches are too long, it is not fan-friendly, it is not promotable, it is not TV-friendly. There are so many issues," Rubin says.

"I think we are a little scared of making true fundamental changes - but we have to."

The ATP Tour's 2020 season begins on 2 January with the newly launched ATP Cup, starting just six weeks after some of the world's leading male players took part in the inaugural Davis Cup finals.

Top female players have a slightly longer break - the season-opening Brisbane International on 6 January comes two months after the WTA Finals finished.

While men's five-set matches are now reserved for Grand Slams and the Olympic final, the length of matches has still prompted plenty of debate.

Tentative attempts to introduce shorter formats of the game have been made - notably with first-to-four-games sets at the ATP NextGen finals and the creation of the Tie Break Tens events, but are yet to break through on the main ATP and WTA Tours.

Uniform change is difficult, however, with seven governing bodies - the ITF, ATP, WTA and four Grand Slams - rarely pulling in the same direction.

"We're at a time where we have to break down the sport of tennis, invest, take a hit for a year or two and bring the sport to a place to where it has never been before," Rubin says.

The WTA says the health and safety of its players - physical and mental - are its "number one priority".

"The WTA has a comprehensive sports science and medicine and athlete assistance support system in place, which is staffed by experienced and expert therapists within the WTA," it said in a statement.

"The WTA provides extensive resources and education to [help] players manage the challenges professional athletes may face, such as performing under pressure, international travel, managing health, public scrutiny, public commentary and 'growing up' in the public eye."

The WTA added that players can receive individual counselling and support if needed from qualified mental health care providers, both at WTA tournaments and remotely.

The ATP said it was "continually looking to build on its duty of care towards its players" and had recently carried out a review of this area with players, team members and industry experts.

In a statement, the ATP said: "Tournament physicians and physiotherapists on the ATP Tour are in continual contact with players and their support teams throughout the year. In cases where a player were to express psychological concerns, we have an infrastructure that would refer them to the appropriate consultant.

"In situations where ATP physios and tournament physicians are concerned about a player's mental, emotional and psychological health, we would recommend that the player seek treatment and assist in the initiation of the appropriate care."

'I had dark times. This sport isn't conducive to happiness'

Passionate, articulate and determined to influence change, Rubin speaks from the heart.

Around the time of this year's French Open, he almost stopped playing a sport to which he has dedicated most of his life. As an 11-year-old, he was said to have been described as "one of the most talented players" fellow New Yorker John McEnroe had come across.

"I didn't know whether I was going to stop for good or just some real time off. I was telling my family and friends that I just don't want to play the sport any more," Rubin remembers.

"I wasn't happy - the sport isn't conducive to happiness. I don't know if I want to throw the word depressed around, but at moments I felt like that.

"I was really thinking this was the end and the last time I was going to hit a tennis ball competitively."

What changed for the world number 212 was spending less time on court, addressing his work-life balance and rediscovering the fun which made him enjoy tennis in the first place.

Rubin moved back to New York from Florida, practised about an hour a day, and then qualified for Wimbledon where he missed out on a third-round meeting with Roger Federer by losing to British youngster Jay Clarke.

Rubin repeatedly makes it clear he still loves the sport, and believes a change of focus - he talks of his love for fashion and photography, as well as still having time for Netflix and HBO - can enable him to crack the world's top 50 next year.

"I started to figure out that it is far more important to put happiness on a pedestal rather than spend eight hours on a court," he concludes.

"I had dark times where I didn't know if I was going to make it out as a tennis player.

"This world of Behind The Racquet has opened up my eyes, it has given me another passion and helped take some pressure of the world of tennis.

"Now I understand it is far more important to be happy."

Rubin pauses as he recalls one story, which he says still gives him "chills".

"It was Jolene Watanabe, who was a top-100 player and played in the Grand Slams in the 1990s. She had cancer, was in remission, and I thought she was going to make it.

"Then I got a message from her husband on Instagram saying 'I just want you to know she is saying her final goodbyes right now and it would be very much appreciated if you could post her story'.

"To hear that they're going through something where she's not going to make it and he was thinking he wanted me to post her story on Behind The Racquet so people could know about it, be a part of it and inspire them... it leaves me speechless.

"To have that kind of impact was something I could not have fathomed, especially this early on, and that's why I keep pushing on."

How it began... and what next?

It was during a sleepless night after arriving home from Australia that Rubin formulated the concept of Behind The Racquet.

After inspiration struck at 3am, he acquired the name of his new project on Instagram, Twitter and Facebook. Within three days he had posted for the first time.

Ten months later, Behind The Racquet has about 35,000 followers across the three platforms, along with a podcast and clothing range as Rubin aims to build the brand.

The next phase is already being worked on, with Rubin aiming to link-up with Talkspace, an online therapy platform which boasts legendary American swimmer Michael Phelps as an ambassador, and the National Association of Mental Illness, as he looks to set up mental health camps for players and perhaps film a docu-series.

Sharing the stories of the sport's biggest names - Rubin hopes seven-time Grand Slam singles champion Venus Williams and US Open runner-up Daniil Medvedev will feature before the end of the year - is another target.

"Not only are many in a sport where they can't make money, they're in a sport where you don't win very often, so they're combining failure on the court with failure financially," Rubin says.

"What I'm really trying to do is pave a way for people that, in five or 10 years from now, are saying 'this is better because of Behind The Racquet'."