Ineos Grenadiers rider Brandon Rivera has fractured his elbow and dislocated a shoulder in Colombia, three days after team-mate Egan Bernal's serious crash in the same area.
Local media report the 25-year-old is being treated at the same clinic as Bernal on the outskirts of Bogota.
Former Tour de France champion Bernal, 25, suffered back, leg, knee and chest injuries earlier this week.
Rivera, friends with Bernal since boyhood, signed for Ineos in 2019.
The pair are both from the city of Zipaquira and met racing on the local mountain-biking circuit.