The stars fell like ninepins on the cobbles of the Hell of the North, as the Tour de France finally exploded into life on the ruptured roads leading from Arras to Roubaix. But the thrills and spills that provided a stream of crashes were at significant cost to the peloton.

Out of the race is Richie Porte, long considered a threat to the defending champion Chris Froome, who crashed soon after the start, and was forced to abandon the race. Out of contention, it seems, is Rigoberto Urán, second to Froome last year, who now has several mountains to climb if he is to challenge the champion. Froome, who also took a tumble, survived, as did his Team Sky teammate Geraint Thomas, now at the head of the ‘virtual’ classification, in the light of the forthcoming Alpine stages which will not favour the current race leader, Greg Van Avermaet.

Richie Porte out of Tour de France after crash on stage nine Read more

Few riders escaped unscathed from a long-awaited stage that was always likely to wreak havoc. There were at times bikes and bodies strewn across the road. Up at the front the cobbled specialists took control with the sprinter John Degenkolb winning the stage from Belgians, Van Avermaet and Yves Lampaert.

“It was a brutal stage, just brutal,” Froome said. “It’s a big relief to get that behind us now, while keeping myself and Geraint at the front, and we’ll soak up the rest day tomorrow.”

The first man to hit the tarmac was Porte, whose disastrous record in the Tour continued as he crashed out before the cobbles were even reached, apparently after colliding with a spectator and dislocating his collarbone. In last year’s race, the Australian crashed out after a high-speed fall on the descent of the Mont du Chat.

The next pre-race favourite in trouble was Romain Bardet, who punctured on the very first section of cobbles and then had to change his bike twice. That set the tone for a torrid afternoon for the French climber, who somehow managed to negate his losses at the finish.

As the stage wore on and the peloton split into fragments, scattered far and wide across the dusty cobbles, the crashes continued.

Facebook Twitter Pinterest Germany’s John Degenkolb celebrates after winning the stage. Photograph: Jeff Pachoud/AFP/Getty Images

Urán’s Colombian compatriot, Egan Bernal of Team Sky, slid painfully through a right-hand bend, while Froome’s own fall, 46 kilometres from the finish, was cushioned by his teammate Gianni Moscon. For the second time in the race, the defending champion had escaped lightly.

Until that moment, Team Sky had seemed in control of a stage that troubled specialists of the pavé and novices such as Bardet, Bernal and Urán.

“We found ourselves in a really good position and kept riding,” Thomas said. “It was just a series of sprints into every sector,” he added. “We were on it all day from kilometre zero. It was only three and a half hours, but it was full gas.

Tour de France: John Degenkolb wins stage nine after wild ride to Roubaix – live! Read more

“Then when the three guys [Degenkolb, Van Avermaet and Lampaert] went I was maybe sixth or seventh wheel. I was like, ‘Ah, maybe I could go,’ but I decided to wait. Maybe if I’d gone everyone would have followed.”

But some, such as Adam Yates’s sports director Matt White, criticised the decision to include so many sectors of cobbled roads in the Tour. “We came through, nobody’s injured, Adam didn’t lose any time but this was a crazy day, a crazy race,” the Australian said.

“A stage like this has no place in the Tour de France. A couple of sectors of cobbles,sure, but we’ve seen guys crash out today.

“There’s a bunch of climbers here who don’t do this style of racing apart from today. So you have a bunch of guys who can handle themselves on the pavé and another bunch, that can’t. That’s the difference.”

But White, like Tom Dumoulin after last Thursday’s stage to Mûr de Bretagne, also accused race officials of turning a blind eye to some blatant drafting by rival teams.

“TV motorbikes were in the way today, and they’ve been in the way a lot this week,” he said. “When they tow multiple guys back on to the peloton – the group of Bardet and Mikel Landa came back through the cars inside the last three kilometres, that shouldn’t happen. You judge if it’s been the same for everyone.”

Yates meanwhile, like Thomas and Froome, is looking forward to the Alps. “I’m excited to finally climb some mountains,” he said, “but most importantly we have a rest day tomorrow, which is fantastic.”

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Monday’s rest day in Annecy ushers in a new phase of this year’s Tour which will surely see Van Avermaet’s days in the race leader’s maillot jaune numbered.

“I’ve made a decent start obviously but now the race is going to change completely,” Thomas said of the mountain stages which begin on Tuesday. “I’m looking forward to it. It would be nice to go into yellow. It would be a good bonus, but there are three big days now so we’ll try and get through that as best we can.”

Thomas, however, refuses to be drawn into any debate over leadership battles between himself and Froome. “We’ll see how these Alps go,” he said. “See how I feel, see how Chris feels and go from there.”

Yet Froome seemed ready and willing to assert his authority. “We’re heading into the mountains now where the real racing starts for me,” he said. “If you had offered me 1:47 off the lead, with none of my general classification rivals up the road, at this stage, I would have taken it. We’re in a good position as we head into the Alps.”