The peloton can be seen taking a slight descent through a town before the Welshman falls without warning, sliding to a stop in a heap further down the road.
News had filtered through during the stage that a loose bidon had caused the crash, and the video shows a number of bottles skittling around beneath the wheels of the peloton before Thomas appears to hit a Bahrain-McLaren bottle, the camera then panning down to show the bidon lying by the side of the road.
Another video from a different angle shows the crash in full, Thomas battling hard to stay upright before he falls and spectators rush over to help.
The 2018 Tour de France winner thankfully got back up and was able to continue, the peloton slowing to allow him to rejoin the bunch.
However, on the approach to the summit finish on Mount Etna, Thomas was detached, his jersey torn and wearing cuts and grazes as he soldiered on, clearly in some discomfort. He eventually finished 12-19 down on stage winner Jonathan Caicedo (EF Pro Cycling), losing more than 10 minutes to his GC rivals and likely out of contention for the maglia rosa.
Speaking after the stage, Ineos sports director Matteo Tossato said: "After one and a half to two kilometres after the neutralised start a bidon went under his front wheel and he crashed. Immediately afterwards he had a lot of pain in his legs, but then on the bike he felt better.
"But in the final 45km it got faster and the climb got steeper and he had a big pain, we preferred for him to drop than take a car to finish the stage and now we wait for the analysis from the doctor."
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