Sebastian Coe's father Peter, who coached the double Olympic champion during his running career, has died aged 88 after a short illness.
London 2012 chief Lord Coe had delayed his arrival in Beijing in order to spend time with his father in hospital.
He arrived in the Chinese capital on Saturday only to hear his father had died several hours later.
Coe, who will return to Britain once the funeral arrangements are known, lost his mother, Angela, in 2005.
A self-taught coach, Peter Coe introduced revolutionary ideas to Coe's training and helped his son win two Olympic 1500m golds, two Olympic silvers in the 800m and break several world records.
Never afraid to speak his mind, he said to his son after Coe's defeat by Steve Ovett in the 1980 Olympic 800m final in Moscow: "You ran like an idiot."
Sebastian Coe said of his father last month: "My father had an extraordinary influence on my life."
Coe junior was 12 when he joined Hallamshire Harriers, and his father soon became convinced that prevailing coaching methods were outdated.
He believed "slow running produces slow runners" and instead introduced to his son's training a programme of short bursts rather than miles and miles at slow pace.
Coe said recently: "The old theory was that to run 800m you had to run 100 miles a week. My dad took that idea apart.
"To run a world-class 800m time you run 80% of the race without enough oxygen, so he started me on a programme which cut the miles to a third but had me running 40 200m consecutively with a 30-second recovery. Or six 800metres."
Coe senior made it his mission to seek out the best knowledge available, he could read coaching manuals from East Germany himself and had Russian ones translated at Sheffield University.
He and his son went on to write several books together about the science and coaching of running.
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