Athletics coach Lloyd Cowan, who guided Christine Ohuruogu to the 400m Olympic title in 2008, has died aged 58.
The former athlete, who specialised in the 110m and 400m hurdles, also coached Ohuruogu to three further Olympic medals, including 400m silver at London 2012, alongside two world titles in 2007 and 2013 in the discipline.
British Athletics said in a statement: "We are deeply saddened by the passing of Lloyd Cowan MBE. Our thoughts are with his family and friends at this time."
Cowan also guided Andy Turner to Commonwealth and European 110m hurdles titles in 2010 before world championship bronze in 2011.
Turner said on social media he was "absolutely heartbroken" by the death of his coach of 12 years, alongside a photo of the pair.
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Writing on Twitter, Turner added: "There will never be another @cowanlloyd, truly one of a kind.
"Lloyd knew me better than anyone, we had some amazing times and even better stories along the way. He made such a huge impact on my life, what a sad sad day."
Cowan, who was appointed as lead sprints coach by UK Athletics in 2013, also guided Shana Cox and Bianca Williams, among several other athletes, to domestic and international honours.
He also coached his son, Dwayne, to world and European 4x400m relay bronze in 2017 and 2018 respectively.
Cowan, who represented England at the 1994 Commonwealth Games, was made an MBE in the Queen's Birthday Honours in 2015.
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