American team EF Education First-Drapac reports that its rider Daniel Martinez was 'punched by a driver' during a training ride in Italy on Tuesday.
The motorist had driven his car close to Martinez during the ride near Pistoia, before later attacking the 21-year-old Colombian and knocking him unconscious.
Martinez was subsequently taken to hospital for medical checks, with the team saying that he was under observation.
"@danifmartinez96 was training today with a group, which was buzzed by a car. Martinez was later punched by the driver, along with another cyclist," said EF Education First-Drapac via Twitter.
"Martinez was taken to hospital, where he remains under observation but is in good condition."
El Tiempo reports that Martinez was riding with a group including fellow Colombians Julián Cardona, also of EF Education First-Drapac, and Miguel Eduardo Flórez of Wilier Triestina-Selle Italia when the incident occurred.
"I was riding here in Italy, and a car wanted to practically kill us," Martinez told El Tiempo.
"In the end, we said he was crazy. He got out and attacked me, gave me a punch in the jaw and left me knocked out. Another friend broke his lip and then he [the driver] ran away."
Martinez signed to the EF Education First-Drapac team for 2018, having previously ridden for Southeast-Venezuela.
He placed second in the 2018 Colombian national time trial, and went on to finish in fifth place overall at the Colombia Oro y Paz. Last week, Martinez placed seventh overall in the Volta a Catalunya, one minute and 29 seconds behind winner Alejandro Valverde (Movistar).
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