Former Yorkshire cricketer Azeem Rafiq says "deep-rooted" racism at the club left him "close to committing suicide".
The 29-year-old ex-England youth captain walked away from cricket after his time at Yorkshire but has now spoken out against the county.
Rafiq has told Sky Sports News he reported incidents of abuse to the Professional Cricketers' Association (PCA) and to senior team officials at Yorkshire before his departure from the club.
Yorkshire have asked independent law firm Squire Patton Boggs to lead the investigation and review into Rafiq's allegations. The club had initially launched a probe on Thursday.
Meanwhile, the PCA have told Sky Sports News: "Rafiq has always been fully engaged and supportive of the PCA and our support systems and we will continue to make these available to him."
In an interview with ESPNcricinfo, Rafiq - a spin bowler who also captained Yorkshire in a Twenty20 fixture in 2012 - said he felt that, as a Muslim, he was made to feel like an "outsider" and left on the brink of suicide.
"I know how close I was to committing suicide during my time at Yorkshire," he said.
Rafiq has told Sky Sports News: "At my worst, I was right on the edge, stood on my balcony. I would regularly come home from training and cry all day. It was a very difficult time for me.
"In one of my first few games, we were going onto the field at Trent Bridge and there was me, Adil Rashid, Ajmal Shahzad and Rana Naved and one of the senior players said: 'there's too many of you lot, it's something we need to have a word about'.
"We would be on nights out, I'd be speaking to someone and I'd have team-mates coming over and saying: 'Don't speak to him. He's a p-word.'
"It's deep-rooted. There were constant social events where I'd leave crying. Sometimes these things get disguised as banter but it stuck with me."
Yorkshire to launch external review into allegations
In response to Rafiq's allegations, Yorkshire chair Roger Hutton issued a statement which read: "Any allegation of this nature is hugely concerning to everyone from the board to the playing staff here, and we take the reports very seriously.
"On Monday this week the club took the decision to launch a formal investigation into the specific allegations made by Azeem Rafiq, and a wider review of YCCC's policies and culture.
"We are in the process of finalising the structure of this investigation and we will be approaching impartial external parties to be part of the review to ensure complete transparency. Further announcements will be made to detail this process in the coming days.
"We fully acknowledge that just as in many walks of life, sport, including cricket and Yorkshire as a club, must do better to fully promote a culture of zero tolerance to racism or any form of prejudice.
"We accepted a long time ago that change was needed at Headingley to improve diversity, especially in terms of racial inclusivity. Since 2014 we've prioritised community engagement with numerous groups right across the county, and across many cultures and ethnicities. While as an organisation we've made real efforts to that end, we are not perfect and it's a work in progress.
"As a player and former captain, Azeem was extremely highly respected and well regarded by the club and its supporters alike.
"Azeem was a gifted bowler and a respected leader of our team, and that was why he became the first British South Asian captain of the Yorkshire T20 side, and the youngest-ever captain of the team.
"We have tried to make contact with Azeem this week to discuss his experiences, and will make further contact in the weeks ahead as it's important that we hear his grievances in as much detail as possible.
"The future direction of our organisation's culture will be best-shaped with the understanding and the input of players, staff and supporters from all minorities and genders, and we will continue this process with the formal investigation that will start in a matter of days and be conducted thoroughly, impartially, and with urgency."
Rafiq is not currently working within the game and admitted his claims will damage his chances of doing so in the future - but insists it was the right thing to do.
"When you're young and coming through, all you're thinking about is trying to go as far as you can in the game," he added. "You have an inkling that if you do say something, it could make it more difficult.
"As time went on I tried to fit in. I did things that I completely regret and it started to take its toll on me. When I stopped trying to fit in I became more and more isolated.
"It angered me that no one put their neck on the line when you could see what was happening. If you see something happening and you don't stop it, in my opinion, that is as bad as the person starting it.
"Something needs to be done now and openness and honesty is the first step to making that change."
ECB 'deeply troubled' by Rafiq's claims
The England and Wales Cricket Board (ECB) say they welcome Yorkshire's commitment to a thorough investigation into Rafiq's claims and praised the former bowler's courage for speaking out.
A statement on Thursday read: "We are deeply troubled to hear of Azeem Rafiq's experiences and recognise the courage it has taken for him to speak out.
"The ECB welcomes Yorkshire County Cricket Club's commitment to thoroughly and urgently investigate this case and the wider review of club policies and culture. We will follow these closely and are in contact with the club and with Azeem. We will consider any further ECB steps which may be appropriate.
"Azeem's story is similar to some of the experiences we have heard about during the Black Lives Matter movement and demonstrates how much work is needed across the game, sport and society as a whole to eradicate racism.
"The ECB is opposed to discrimination of any form and remains committed to making the changes needed to make cricket a game for everyone.''
In their statement, the PCA added: "The PCA has provided support to Azeem throughout his playing career and since he has left the game. He has always been fully engaged and supportive of the PCA and our support systems and we will continue to make these available to him, as we do all our members.
"The PCA is currently conducting a survey of our membership to understand wider views of racism in the professional game.
"This is part of our strategy and commitment we have made earlier this year, driven by the Black Lives Matter movement and questions raised by our members on the PCA's role in addressing the issues of equality, diversity and inclusion in cricket."
'Azeem's experience is disappointing and concerning'
Former England international Ajmal Shahzad, who played the majority of his domestic career with Yorkshire, says it is important that Rafiq's claims are thoroughly investigated.
"It's very disappointing and concerning to hear of Azeem's experience, particularly the impact that it has had on his mental health," said Shahzad, who is now head coach of the MCC.
"I understand that YCCC/ECB have responded to Azeem which is a positive start and hopefully a catalyst for further productive dialogue. It's now important that the matter is investigated in a thorough and professional way.
"The topic of inclusion and diversity is rightly at the forefront of our minds at present and Azeem's experiences highlight the responsibility that we all have for delivering change and also the size of the task ahead of us.
"As you will appreciate due to the formal inquiries that are currently in process, I am unable to comment further on this matter however I am confident that these will be thorough open and transparent."
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