Tony Martin of Etixx-Quick Step, tantalisingly close to taking the lead of the Tour de France in the past two days, attacked with 3 kilometres left of today's Stage 4 to Cambrai to finally get into the yellow jersey, a day that took the race across some of the cobbled sections used in Paris-Roubaix.
The German rider takes over the race lead from Team Sky's Chris Froome, who led him by one second this morning, and whose principal aim would have been to make it through today's stage unscathed, having not even made the first cobbled section 12 months ago when he crashed out of the race on Stage 5.
Geraint Thomas had led Froome off the seventh and final section of pave a little more than 10 kilometres from the finish at the head of a group of eight riders including defending champion Vincenzo Nibali of Astana.
With a group containing Alberto Contador of Tinkoff-Saxo and Movistar's Nairo Quintana behind them on the road, it briefly seemed that there might be an opportunity for both to take time off their principal rivals for the overall.
Froome clearly wanted to force the pace, but he wasn't getting any help and the two groups came back together, with Tinkoff-Saxo's Peter Sagan and Paris-Roubaix winner John Degenkolb of Giant Shimano seemingly set to fight it out for the sprint.
However, Martin - who had needed to grab a bike from team mate Matteo Trentin in the closing 20 kilometres after puncturing - gave them the jump and rode away to victory. Sagan prevailed over Degenkolb to clinch second on the stage.
For Team Sky and Froome, who had the burden of keeping the yellow jersey safe through today's stressful stage from Seraing - the 2013 champion narrowly avoided hitting a kerb as he was pushed wide ahead of the fifth section of cobbles - loisng the race lead means less pressure in the coming days as the race heads across northern France to Brittany then the Pyrenees.
Froome remains second overall, 12 seconds behind Martin, with BMC Racing's Tejay van Garderen remaining third. One of France's pre-race hopes for the GC, Fdj.fr's Thibaut Pinot, had a less happy day, turning down a team mate's bike following a mechanical issue, having ealrier been shown on TV giving a team mechanic an earful after receiving assistance.
As in Paris-Roubaix, the sections of pave today were numbered in reverse order, and as in the Queen of the Classics there was a lot of jostling in the front group ahead of each of them as riders sought to find the best line at the head of the group - but today, some teams were focused on looking after their overall contenders, rather than looking for the win.
Stage 4 winner Tony Martin of Etixx-Quick Step
Taking the yellow jersey after all the bad luck I've in the last three days, and also today with the flat tyre towards the end, it's a super nice story and it makes me super happy. Matteo Trentin gave me his bike straight away after I punctured, then I had to be focused because it wasn't my bike, I had some difficulties to brake and I had lost a lot of energy in the chase.
Michal Golas did a great job bringing me back to the front group. This morning Tom Boonen gave me a call to talk about the cobblestones and Eddy Merckx motivated me on the start line but I'm definitely surprised to win this stage and take the yellow jersey, especially after the puncture.
Everybody in the group thought I was at the limit and I was! Nobody expected such an early attack but with 4km to go, all riders were on their knees. It was the right moment for me to attack. I found some extra power. I came here for training for two days, so I knew that I had a chance if I could make it to the last kilometre, then it was more technical.
My emotions of the past four days have been a roller-coaster. I've missed the yellow jersey by seconds. My goal was to get it on the first day. I was super upset that I didn't. The pressure was getting higher every day. I really wanted the yellow jersey for myself and for the team.
My goal now is to keep the yellow jersey till the first rest day. There are a few hard finales but normally, I should be able to stay at the front and we're also one of the favourites for the team time trial. I'm pretty sure I have a fair chance to remain in the lead until the Pyrenees.
Chris Froome of Team Sky, now second overall
I was trying to show how strong I was on the cobbles today, it was about staying out of trouble. When it got over 200km it was more about who had the legs, and after the last section I had Geraint [Thomas] ahead of me so we thought ‘why not?’, and I had a little attack. My legs felt good but unfortunately it all came back together.
Congratulations to Tony [Martin] for his late attack. He’s been really close to the yellow jersey for a few days now and he deserves this after all the hard work he’s put in.
I’m not concerned about losing the yellow jersey. There’s a long way to go, and while Tony’s a great time triallist, he’s not going to be there in the mountains, so I’m happy to see the jersey go to him rather than any of the big overall rivals.
This is the perfect situation for us and it will hopefully mean my guys can have a bit of a rest over the next few days now.
We can all let off a big sigh of relief after today. It was a stressful stage and sketchy on the cobbles, and I know we’ll all be sleeping a lot better tonight.
Defending champion Vincenzo Nibali of Astana, whose performance on the cobbles in the rain last year helped set up his overall win
We haven't changed anything compared to last year, only the weather has changed. On the last slightly uphill pavé section, I've tried to break the group hoping that someone would get dropped. It was a very difficult race.
At the end we were all the favourites together and we managed to handle the stress of such a specific stage. I've received a great support from the team.
But it was dry, so it was less dangerous than last year and it wasn't possible to create difference because we were riding in only one direction. So the maximum effect of the accelerations at the front was to put the whole group in one lane.
I couldn't do any more. I'm satisfied to not lose more time today. After those first few stages, I feel physically well. I have a deficit to recover and I'll try every time there'll be an occasion.
Simon has been news editor at road.cc since 2009, reporting on 10 editions and counting of pro cycling’s biggest races such as the Tour de France, stories on issues including infrastructure and campaigning, and interviewing some of the biggest names in cycling. A law and languages graduate, published translator and former retail analyst, his background has proved invaluable in reporting on issues as diverse as cycling-related court cases, anti-doping investigations, and the bike industry. He splits his time between London and Cambridge, and loves taking his miniature schnauzer Elodie on adventures in the basket of her Elephant Bike.