The Dimension Data rider was starting his third race of the season and hoping to add to the victory he picked up at the Dubai Tour at the start of February, but hit the deck before the official start of the 189km opening stage between Madinat Zaya and Adnoc School.
Despite remounting his bike and trying to continue with the race, Cavendish climbed off just five kilometres into the stage, being taken away for a medical check where the full extent of his injuries will be assessed.
According to his team, Cavendish fell on the same shoulder as he injured in his crash with Peter Sagan on stage four of the 2017 Tour de France, with team-mates looking concerned as they gathered around him sitting on the tarmac.
Cavendish broke his right shoulder blade in the Tour crash on July 4, 2017, an injury which put him out of action for two months, only returning to action at the Tour of Britain in September.
However the team later announced that Cavendish’s injuries consisted of concussion and whiplash, with a serious injury to his neck having been ruled out.
Race officials blamed the automatic sensors on an official car for making it brake, causing a ripple effect through the bunch that led to a touch of wheels and Cavendish coming down.
Cavendish’s abandon means that his Dimension Data team will likely support Mark Renshaw in the sprint stages of the WorldTour race.
The opening stage of the Abu Dhabi Tour sees the riders cover 189km between Madinat Zaya and Adnoc School, with a flat finish that should see the remaining sprinters in the race battle it out for victory.
Stages two and three should also see bunch sprints at Yas Beach and Big Flag, before the general classification is decided with an 11 kilometre individual time trial on stage four, and a summit finish to Jebel Hafeet on stage five.