Alberto Contador has been admitted to hospital in Bogotá, Colombia, with a fever and severe gastrointestinal problems.
The 36-year-old was in Colombia to take part in the Giro de Rigo, a cycling event being promoted by EF Education First's Rigoberto Urán, but confirmed in a video appearance that he would no longer be able to take part.
"I regret not being able to take part in the Giro de Rigo," Contador said. "I had trained with great enthusiasm and travelled [to Colombia] with great enthusiasm but during the trip I began to feel ill, suffering from very high fevers."
The Spaniard says he expects he may have suffered a severe form of food poisoning after eating something that did not agree with him.
"I must have eaten something contaminated. Now we are trying to stabilise [me]," Contador said.
The seven-time Grand Tour winner will remain in hospital in Bogotá for the next 48 hours as doctors continue to observe his condition.
Other pro riders set to take part in the Giro de Rigo include Tour de France 2019 winner Egan Bernal (Ineos), Esteban Chaves (Mitchelton-Scott), Sergio Higuita (EF Education First), Daniel Martínez (EF Education First), Sergio Henao (UAE Team Emirates) as well as former pros Luis Herrera and Iván Basso.
In August, Contador broke his own climbing elevation record at an Alpine endurance race, having continued to enjoy riding his bike despite retiring from the professional peloton in 2017. The Spaniard ascended more than 7,000m in the gruelling nine hour Tour des Stations at an average speed of 23.4km/h.
A number of former riders have been hospitalised recently, Eddy Merckx spent a week in hospital after suffering a haemorrhage following a bike crash during a Sunday ride with friends. The Belgian's former rival Roger De Vlaeminck then found himself in intensive care with a fever, while Raymond Poulidor also spent time in hospital to receive treatment.
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