The stage began with the confirmation that Britain's Geraint Thomas had withdrawn from the year's second Grand Tour.

Thomas came into the race among the favourites, but the 2018 Tour de France champion saw his hopes end yesterday in a crash which saw him lose over 12 minutes yesterday.

Scans this morning revealed he had an undisplaced fracture of his pelvis, following a heavy crash in the neutral zone of stage three.

“It’s so frustrating, I’d put so much work in to this race," said Thomas.

“I did everything I could and feel like I was in just as good, if not better shape, than when I won the Tour.

“I was feeling really good, so for it just to end like this is gutting.

“I was really up for starting today, I woke up and wanted to start with the boys and at least help them go for stages over the next few days, but deep down I knew something wasn’t right, so we went to get these extra scans.

“It does make the decision easier when there’s a fracture in some ways, because obviously I don’t want to do anymore damage.”

The 140 kilometre fourth stage from Catania to Villafranca Tirrena was expected to conclude with a bunch sprint, should the sprinters remain in the peloton after the Portella Mandrazzi climb at the halfway point in the stage.

Colombia’s Fernando Gaviria was among the pre-stage favourites to be dropped, with the UAE Team Emirates rider unable to regain contact.

Demare was among the beneficiaries as the Italian sprinted to victory at the conclusion of the stage in 3 hours, 22min and 13sec.

Demare was forced to wait to confirm his second Giro d’Italia stage win, with officials assessing a photo finish with Slovakia’s Peter Sagan and Italy’s Davide Ballerini having finished alongside the Frenchman.

Sagan ultimately was left in second place for the second time in four days, while Ballerini placed third.

“After I crossed the finish line I was not sure I had won,” Demare said.

“I saw Ballerini celebrating, so I thought I was second and could not celebrate until my success was made official on the podium.

“I am super happy.

“It was a special finish, we wanted to keep the high speed at the front as Gaviria and Viviani were 25-30 seconds behind.

“In the final kilometre, teammate Miles Scotson accelerated very fast and tried to go solo, Cofidis had then to work to catch him and I could save some precious energy for the final sprint.

“Today I had good legs but also some luck on my side.”

The general classification remained unchanged with Portugal’s Joao Almeida leading by two seconds from Ecuador’s Jonathan Caicedo.

A bizarre incident saw Vini Zabù-Brado-KTM riders Etienne van Empel and Luca Wackermann crash in the final kilometre.

Wackermann was taken to hospital with the team saying he is conscious.

The team’s general manager Andrea Citracca suggested to Italian TV station RAI2 that the crash had been caused by barriers being blown across the road by a helicopter, which was claimed to have flown too low.

Tomorrow’s stage will see the riders complete a 225 kilometre route from Mileto to Camigliatello Silano.