It caused the Dimension Data rider to fall heavily in the roadside barriers, leaving him bloodied and fearing his race may be over.

The crash happened as riders begun to launch their sprint to the line and move towards the right-hand side of the road, with Cavendish making contact with Bora-Hansgrohe’s Sagan before hitting the barriers.

Sagan managed to remain upright after the collision and had initially finished in the runners-up spot, lifting him to second in the general classification, seven seconds behind Team Sky’s Geraint Thomas.

Soon after the race though, the Slovankian was disqualified having appeared to have caught Cavendish with his elbow.

"We decided to disqualify Peter Sagan from the 2017 Tour de France because he endangered seriously several other riders, including Mark Cavendish, in the final meters of the sprint which happened in Vittel," race jury President Philippe Marien said.

"We apply article 12.104 of the International Cycling Union regulations which allow us to disqualify a rider."

Cavendish required medical treatment on the ground before crossing the finish line with his right hand bandaged.

The Briton landed heavily on the right shoulder he injured when crashing out of the opening stage of the 2014 Tour de France in English town Harrogate.

Cavendish revealed that Sagan, the world road race champion in 2015 and 2016, apologised afterwards. 

"I get on well with Peter and a crash is a crash but I'm not a fan of him putting his elbow in," the 32-year-old was reported as saying by BBC Sport after the race, with his right arm in a sling.

"I need stitches in a finger.

"It's something to do with the shoulder that I hurt in Harrogate. 

"I'm not a doctor but I'm not optimistic."

Sagan, winner of the points classification at the Tour de France for four consecutive years since 2012, claimed Cavendish "was coming from behind" and that he "did not have time to react and go left".

Roger Hammond, the sporting director of Cavendish's Team Dimension Data, tweeted an overhead view of the incident in the aftermath. 

He wrote: "Causes a big crash at 1.5 to go, elbows fellow competitor in the head 300 meters... can only result in one decision. #Goodbye".

Causes a big crash at 1.5 to go, elbows elbows fellow competitor in the head 300 meters... can only result in one decision. #Goodbye pic.twitter.com/xeTB0llOPF

— Roger Hammond (@rog10) July 4, 2017

It was second major crash in the last two kilometres of the 207.5km stage from Mondorf-les-Bains to Vittel.

The first had occurred with much of the middle of the peloton coming down on the left-hand side of the road.

Among those involved was another Thomas, another Briton and overall race leader.

The Team Sky rider retained the yellow jersey in spite of the crash having been able to finish safely.

As the crash happened in the final three kilometres on a designated sprint stage, under the rules he was credited with the same time as the stage winner and retained the yellow jersey.

France’s Arnaud Démare won the stage after crossing the line in 4 hours 53min 54sec, securing the Française des Jeux rider's first victory in the sport’s flagship event.

Chris Froome, the defending champion, is 12 seconds off the pace in the general classification in second place.

The Briton is targeting a fourth Tour de France title having won three of the last four editions, in 2013, 2015 and 2016.

Action is due to continue tomorrow with stage five, a 160.5km stage from Vittel to La Planche des Belles Filles.

Racing is scheduled to draw to a conclusion will the traditional sprint stage at the Champs Elysees in Paris on July 23.