Tom Dumoulin says his Giro d'Italia general classification challenge is over after he crashed during stage four on Tuesday.

Team Sunweb rider Dumoulin was involved in an incident 4.5 kilometres from the end of the 235km ride from Orbetello to Frascati.

The 2017 Giro champion was left with blood streaming from his knee and could not return to the peloton after picking himself off the deck.

Dumoulin crossed the line with his team-mates four minutes and five seconds behind stage winner Richard Carapaz before heading for an X-ray, which cleared him of any fractures.

The Dutchman trails Primoz Roglic by four-and-a-half minutes and has ruled out having any chance of regaining the Maglia Rosa.

Dumoulin said: "[Salvatore] Puccio from [Team] Ineos crashed, I think he touched a wheel or something and he took me and [Ion] Izagirre with him. I was in the front of the bunch and just couldn't avoid it.

"There are no fractures, which is good, but my knee is very swollen. I wasn't able to push any power in the last few kilometres so I don't know how I will be tomorrow; the GC is for sure gone."