Tom Dumoulin helped Koen Bouwman claim his first career Grand Tour victory from a breakaway as Jumbo-Visma's switch to target stage wins delivered quick results on stage seven of the Giro d’Italia.

After a brutal day in southern Italy, in which the peloton tackled a rolling stage featuring 4,500 metres of climbing at an often relentless pace, Bouwman had the power to ride clear of Bauke Mollema and Davide Formolo on the short, sharp climb to the line.

Three days after losing nine minutes on Mount Etna to show he is not in shape to contend for the overall title this year, 2017 Giro winner Tom Dumoulin played a key role in his team-mate’s victory before rolling over the line in fourth place.

They finished just under three minutes ahead of the chasing peloton with no major splits between the overall contenders, meaning that Juan Pedro Lopez retains the pink jersey for another day.

Simon Yates sits fourth, one minute 42 seconds down and the best placed of the overall favourites.

Koen Bouwman reacts after winning the seventh stage

Though ranked as a medium-mountain stage, this day would have felt worse than many of the big climbs still to come given the unrelenting nature of the terrain on the 196km road from Diamente to Potenza.

A furious fight to form a breakaway meant there was no let up in pace for well over an hour as attacks flew, and no group being able to establish itself until seven riders finally got away with a little under 130km to go.

They built a lead of over five minutes which held until the two biggest tests, Monte Sirino and the Montagna Grande di Viggiano, were behind them and they began to attack each other with 30km to go.

Dumoulin and Bouwman worked it nicely to ensure they still had the numbers on the descent towards Potenza, and that advantage was crucial as the games began approaching the ramp to the finish, with Dumoulin setting a place Bouwman could force the others to chase by letting his team-mate’s wheel go.

"It’s unbelievable," said Bouwman, who was the only rider in the front group without a Grand Tour stage to his name, and only one previous professional win.

"I can’t believe it. It was such a hard day. Tom did a superb job in the last two kilometres and I found myself feeling quite good. One time on the climb I had trouble but I could come back so I was confident for the sprint.

"It was steeper than I thought when I started my sprint but I felt I had so much power left. I looked behind me and saw I had a big gap, perfect."

This day was one for the sprinters simply to survive, but there was bad news for Mark Cavendish before it even began as Michael Morkov, QuickStep-AlphaVinyl’s supreme lead-out man, did not start the stage after developing a fever overnight.