David Moorcroft has resigned as chief executive of UK Athletics.
Moorcroft is still the British 5,000m record holder
The 53-year-old, in charge of British athletics since 1997, has come under increasing fire after a string of disappointing international results.
"I am convinced I am taking the right decision - it is time to let someone new take the helm and lead the sport to London 2012," said Moorcroft.
Track legends Lord Sebastian Coe, Steve Cram and Daley Thompson have been tipped as candidates to take the role.
And the pressure on Moorcroft's successor will be intense ahead of the 2012 Olympics, to be hosted by London.
But Moorcroft will be staying on for a time to ensure a smooth transition.
It has been hugely encouraging to see a number of young talented athletes emerging
Britain won just one gold medal at the 2006 European Championships, by far their lowest total for 20 years and a pale return compared to the nine golds won in 1990 and 1998.
"I am proud of the UK Athletics I am leaving behind," said Moorcroft, who had financial success stories, including a £50m sponsorship deal with Norwich Union this year.
"Athletics now has the system, funding, facilities and, most importantly, the people in place to take the sport into the next phase of its development.
"It has also been hugely encouraging to see a number of young talented athletes emerging on the international scene over the last year.
"These athletes will be in their prime in 2012 and athletics in the UK is now in the position to support their aspirations."
David Moorcroft has made a first-class contribution to athletics
Minister for sport
Moorcroft was praised as a "man of integrity" by minister for sport, Richard Caborn.
"Moorcroft has made a first-class contribution to athletics in this country, both as a world record-breaking competitor and as an administrator," said Caborn in a statement.
"He came into UK Athletics at a very difficult time for the sport and leaves it financially in a much healthier state and with our next generation of young stars performing well in Gothenburg and at the World Junior Championships."
British Olympic Association chief executive also hailed Moorcroft's contribution and predicted that his experience would see him headhunted by other sporting bodies.
"He has achieved much in the sport since he took over nine years ago, just as the sport went into administration," said Clegg.
"I am confident that his skills and experience will be sought elsewhere in sport, particularly in the build-up to the 2012 Olympic Games in London."
UK Athletics president Lynn Davies said: "Dave has given so much to athletics in this country. He has secured the financial solvency of the sport and had a key role in its restructuring.
"The whole of the athletics community now needs to come together and collectively step up and meet the biggest challenge in our sport's history."