Manchester City chief executive Garry Cook has resigned over claims he emailed defender Nedum Onuoha's cancer-suffering mother mocking her illness.
Cook offered his resignation after an investigation by City found "there is foundation" to the allegations.
He had denied sending the message, claiming his account was hacked.
GARRY COOK FACTFILE
Moves to the United States
Joins sportswear firm Nike. Heads up Brand Jordan, working with basketball star Michael Jordan
- May 2008:
Recruited by new Man City owner Thaksin Shinawatra as chief executive
- June 2008:
Appoints Mark Hughes as manager after Sven-Goran Eriksson is sacked
- September 2008:
Club taken over by Abu Dhabi United Group, with Cook heading up player recruitment. Brazilian Robinho signs record £32.5m deal
- January 2009:
City bring in Wayne Bridge, Craig Bellamy, Shay Given and Nigel de Jong but fail in bid for Kaka
- Summer 2009:
City keep spending under Cook as Carlos Tevez, Roque Santa Cruz, Gareth Barry and Emmanuel Adebayor all join
- November 2009:
Cook mistakenly welcomes City legend Uwe Rosler to "the Manchester United hall of fame" at a club gala
- December 2009:
Mark Hughes leaves City and is replaced by Roberto Mancini
- July 2010:
Cook jots down a list of player targets on a napkin at a meal with Oasis singer Noel Gallagher in South Africa
- September 2011:
Resigns as chief executive
issued a statement
confirming the board had accepted Cook's resignation and that chairman Khaldoon Al-Mubarak had apologised to Dr Onuoha.
Defender Onuoha's mother, who acts as his agent, had previously sent a message to Marwood and Cook, explaining that while she was "ravaged with cancer" it would not prevent her negotiating on behalf of her son.
Dr Onuoha then received an email, allegedly from Cook and addressed "Brian", which apparently ridiculed her use of language in describing her illness.
The email is reported to have read: "Ravaged with it!!...I don't know how you sleep at night. You used to be such a nice man when I worked with you at Nike. G".
Dr Onuoha told the Sun the email had left her "humiliated and devastated".
The claims led City's board to launch an investigation and, following its findings, Cook offered his resignation and Khaldoon wrote to Dr Onuoha "to apologise for any distress caused".
In the statement, Khaldoon said: "Garry has made a remarkable contribution to Manchester City Football Club over the past three years. His judgement in this matter should in no way lead to his accomplishments being overlooked.
"On every level, the club is unrecognisable from the organisation which he inherited and our staff and supporter services, community outreach and commercial activity have seen unparalleled growth under his direction with yet more projects to be realised on the horizon.
Man City chairman Khaldoon Al-Mubarak
“Garry has made a remarkable contribution to Manchester City Football Club over the past three years. His judgement in this matter should in no way lead to his accomplishments being overlooked”
"On behalf of Sheikh Mansour and the Board, I would like to thank him for his energy and tireless commitment to serving all those connected with the football club. He will always be welcome at Manchester City."
Cook said: "I am privileged to have held my position at Manchester City Football Club and to have experienced the opportunities that it has presented.
"The privilege is in part offset however by the significant personal focus which has at times, detracted from the magnificent achievements of those working at the football club.
"It is that factor, together with my error of judgement in this matter that has prompted me to reach this decision, which I believe is in the best interests of the football club."
City director John MacBeath will fill the role of temporary chief executive officer while a replacement is sought.