The managing director of the 2017 world athletics championships has left the organising committee, becoming the third board member to leave in less than a week.
Sally Bolton, who joined the committee in 2014, follows deputy chair Heather Hancock and audit committee chair Martin Stewart in walking away from organising the event.
Bolton said: "I'm incredibly proud of the work that has been completed in achieving the early milestones that lay the foundations for the event's success.
"I wish the team well in what is going to be an exciting 18 months, and I look forward to seeing some amazing sport take place at next year's championships."
According to reports, the departed trio failed to see eye to eye with chairman Ed Warner and chief executive Niels De Vos.