Lawn Tennis Association president Martin Corrie has resigned after an investigation found the way a committee he was on dealt with a sexual assault allegation was "not good enough".
An independent investigation criticised Hertfordshire LTA's handling of an allegation made in 2004 by a player against a coach, relating to the 1990s.
Corrie was a member of Hertfordshire's Executive Committee at the time.
He temporarily stood down as LTA president in March 2018.
Corrie, who will not face a full disciplinary hearing after resigning, admitted the matter should have been handled differently at the time.
The LTA "sincerely apologised" for its failings.
The independent investigation found that the communication between the LTA and Hertfordshire LTA was "not good enough" during the 2004-05 investigation into the allegation.
The accused coach was sanctioned and his licence to coach children was revoked following an LTA enquiry in 2005.
"The independent investigation established failings in the way the matter was handled between the LTA and the Hertfordshire LTA Executive Committee, for which we sincerely apologise," said LTA chief executive Scott Lloyd in a statement.
"We will continually work to improve safeguarding standards and provide support to any members of the tennis community with concerns."