Wilco Kelderman turned out to have suffered not only a concussion, but also a fracture in his spine during a fall during a training camp.
His new team BORA-hansgrohe reports this on Sunday.
Kelderman was hit with a number of teammates on Saturday during a training ride in Italy.
BORA-hansgrohe already announced that the 29-year-old Dutchman had suffered a concussion from this.
Several teammates were involved in the collision, including Germans Andreas Schillinger (broken vertebrae) and Rüdiger Selig (broken vertebrae) were taken to hospital.
It is not known exactly how the incident happened in Italy.
Dutchman Ide Schelling, who was also on a training camp but escaped a fall, announced on Saturday that "there was a major crash with a car".
His injuries are bad news for Kelderman, who had bad luck during his career and wants to continue the good course of last season at BORA-hansgrohe this year.
He finished third in the Giro d'Italia, among other places.