English jump jockey Liam Treadwell, who rode 100/1 outsider Mon Mome to victory in the 2009 Grand National, has died at the age of 34, it was announced on Tuesday.
"We're deeply saddened to hear about the passing of 2009 Grand National-winning jockey Liam Treadwell," said a post on the Twitter feed of Aintree Racecourse, the Liverpool course that is home to the feted race.
"Our sincere condolences to his family and friends at this difficult time."
Treadwell returned to the saddle after initially retiring from professional riding in February 2018.
Few of his winners, however, were a bigger shock than when he rode Mon Mome to National glory for trainer Venetia Williams.
No cause of death has yet been announced.
A statement from West Mercia Police said officers were called to an address following the death of a man.
"The death is currently being treated as unexplained. However, at this stage there is believed to be no third-party involvement," said a police statement.
Liam Treadwell wins the 2009 Grand National on Mon Mome
Liam Treadwell, pictured after riding 100/1 shot Mon Mome to victory in the 2009 Grand National, has died aged 34