Roger De Vlaeminck is in intensive care, having been admitted to hospital with a fever on Saturday morning.
The 72-year-old has said he is "doing well now" but will remain in hospital while doctors conduct further tests on the Belgian.
"I had already had cold shivers on Friday evening," Vlaeminck told Belgian newspaper Het Laatste Nieuws. "Saturday morning I still didn't feel well. I had a fever of 39 degrees and decided to go to the hospital. I must certainly stay there for the next 48 hours for extensive examinations of the heart, lungs, etc. They want to fully screen me to find out the cause of my illness."
The four-time Paris-Roubaix winner says his condition is improving and he is no longer in pain: "Considering all circumstances, I am doing well right now," De Vlaeminck says. “The fever has subsided and I also feel no pain. Although it has settled on my neck muscles a bit."
Vlaeminck is the third cycling great to have recently been admitted to hospital, with Raymond Poulidor, hospitalised last week, with his family initially “very worried” before his condition “improved significantly on Friday following treatment.
Then, Eddy Merckx was also taken to hospital with a head injury after falling off his bike during a ride with friends.
The 74-year-old was rushed to hospital in the Flemish city of Dendermonde, Belgium, as a precaution, with further examinations of his condition set to take place. A friend who had contact with his wife telling Belgian broadcaster Sporza: "I had contact with his wife last night. According to her it’s all-in-all good."
During his career, De Vlaeminck also won Liège-Bastogne-Liège, Milan-San Remo three times, the Tour of Lombardy twice and the Tour of Flanders, as well as 22 stages in the Giro.
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