With a dozen days of racing left in the coronavirus-shortened Grand Tour, McCarthy crashed at high speed during the 159.7km stage from Vitoria-Gasteiz to Villanueva de Valdegovia.
The peloton was chasing behind a large breakaway across a plateau between the day's two category 1 ascents of the Puerto de Orduña when McCarthy was spotted by television cameras on his back in the middle of a farmer's field, his bike alarmingly far away from the road the race was on, indicating the fall had come at a high speed.
The Bora-Hansgrohe car as well as medics were quick to stop and attend to the 28-year-old rider, who was forced to abandon the race. Out of caution, he was strapped to a backboard and taken by ambulance to hospital for tests.
The team later announced that doctors ruled out any head or spinal injuries, and found no broken bones.
"He has suffered a severe distortion of the knee, which leads us to assume a complicated ligament injury of the right knee joint. An evaluation of the imaging is still pending at this time," the team said.
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