When the race arrived at the last cobbled section, d'Hélesmes à Wallers, there were three riders at the head of the field, Lars Boom (Belkin), Vincenzo Nibali and Jakob Fuglsang (both Astana). Boom used those final cobbles to power away from the Astana riders and solo away for a memorable win. His first ever Tour de France stage victory has come at a good time, as the Belkin team is suffering from sponsorship concerns and Boom may well be searching for a new employer after the Tour de France, a search that will be greatly facilitated after this victory. It also made up for Boom’s misfortune earlier in the year, when a crash in Paris-Nice left him short of fitness for the classics. Behind Boom, Nibali and Fuglsang were focused on maximising their lead over the pursuing groups; they weren’t racing for a stage win, rather they were racing for a commanding hold on the Yellow Jersey on a seismic day of racing.

After the race Boom made it clear that the abysmal conditions were perfect for him. “This was an epic stage! For many years, I've dreamt of a wet Paris-Roubaix and I got what I wanted today at the Tour de France." He also made reference to the difficulties he had endured earlier in the season: "This morning, when I saw the weather, I smiled a bit. I was relaxed and confident all day. In the last corner, when I looked back and realized that I was going to win, I was shaking my head because it was an amazing feeling. I've been unlucky earlier this year. I had a broken elbow. This win is what I needed for my career.”

In the build-up to this fifth stage had been a nervous and apprehensive mood about the effect the cobbles might have upon the General Classification riders. That anxiety grew as the weather conditions deteriorated, to the point that rider safety concerns prompted the organisers to remove two of the nine planned cobbled sections prior to the start. The concerns about this stage would prove well-founded with crashes, mechanical problems and time gaps galore, on a hugely exciting stage.

However it’s arguable that the greatest damage was done before the race had even reached the first cobbled section, as treacherously wet roads raised the nervous feeling in the peloton to fever pitch. As a result, strong pace setting by Cannondale and frequent crashes, had split the peloton into several groups ahead of the first cobbled section; leaving Chris Froome’s (Team Sky) race in ruins in the process.

Sporting considerable support on both wrists, a legacy of his crash yesterday, Froome was one of the first riders to run into difficulties, coming down hard on the slippery surface during one small pileup. Team Sky rallied around their leader, dragging him back to the peloton and pushing their way to the front in an effort to avoid further trouble. That didn’t work though, as further crashes first took out his support, then Froome himself. Unfortunately this time there would be no chasing back on, as a clearly distressed Froome was forced to abandon the race and climb into a Team Sky car. It was a sad way for the defending champion to leave the Tour de France, and the racing in the mountains will be poorer for his absence.

Team Sky manager Dave Brailsford was understandably upset when speaking after the stage. “He's out of the race. Obviously it's devastating for Chris and for the team. We knew it was going to be a tough race. We really believed in Chris and his ability to win this race. But it's not to be this year. In Richie Porte, we have a very capable, viable leader in the team. When you have a day like today, when you have a setback you have to roll ahead and go again, you have recalibrate your goals and you go again. Richie Porte came on the Tour to be the team leader number two and he showed great ability to ride the cobbles the way he did,”

The racing had been frantic ahead of the opening section of cobbles, but once it had passed there was something of a hiatus as several groups came together to form one large peloton. Yet that hiatus proved all to brief, as the race would explode upon the second section of pave. Vincenzo Nibali, Andrew Talansky (Garmin-Sharp), Michal Kwiatkowski (Omega Pharma-Quick Step) and Jurgen Van den Broeck (Lotto Belisol) found themselves in a group with team mates and classic specialists, and well ahead of Alberto Contador (Tinkoff-Saxo), Alejandro Valverde (Movistar) and the rest of the GC riders. From that point on the race pattern was set, Nibali, Fuglsang and, once they had reeled in the break, their impressive team mate Lieuwe Westra, rode as fast as they could manage, while the various groups behind chased as well as they could. Crashes for Talansky and Van den Broeck and attrition slowly reduced the leading group, and one final push by the Astana riders dislodged specialists such as Peter Sagan (Cannondale) and Fabian Cancellara (Trek Factory Racing), leaving just Nibali, Fuglsang and Boom in front on the approach to the final cobbled section.

For Nibali and his Astana team this stage was an unqualified success. They gained huge chunks of time over all of the main contenders for the Yellow Jersey, Froome is out of the race, the majority of the GC contenders are between 1:45 (Van den Broeck) and 2:37 (Contador) down on Nibali; with Kwiatkowski (0:50) and Fuglsang (0:02) the only potential contenders closer.

After the race Nibali said: “I'm delighted with the outcome of today's stage. It was a really stressful day and a very hard race. I wasn't thinking of the yellow jersey. I was just focused on riding the best I could." While he also acknowledged the roles that Fuglsang and Westra played: "I've lost some team-mates who slipped but at the end, it was still a great team work with Jakob Fuglsang and Lieuwe Westra who went in a breakaway to be able to help me in the finale as he fantastically did. It went all well. I didn't think I would distance Contador so much today. But I'll keep my feet on the ground. I want to remain quiet. It's still a long way away with lots of mountains and everybody has seen today that crashes can happen.”

For the rest of the contenders it was rather disastrous. It will take time to count the true cost of this chaotic stage; the time gaps are obvious, but the full tally of injuries and illnesses (an inevitable consequence of racing so hard in such foul conditions) won't be known for a couple of days. Speaking after the race Contador said: "It was a complicated day. We lost some time and we're certainly going to try and get some back in the days ahead. But the most important thing if that we finished the day without crashing. We now have to recuperate well."