My legs are covered in dust, I’ve got an irritated throat, my feet ache and I’m pretty exhausted. And I was just spectating on the cobbles.

The experiment of taking the Tour de France on to the rough roads of northern France worked brilliantly today after the race was treated to a thrilling spectacle that turned the classification on its head and will no doubt change the dynamics of the race all the way to Paris.

There were plenty of worried riders ahead of today’s stage. Even Tom Boonen, a triple winner of Paris-Roubaix who pulled out of the Tour with tendonitis, said there was no place for these bone-shaking cobbles in the Tour de France. There were always going to be winners and losers today, but they weren’t exactly who we expected.

It was an epic stage, just what was needed after the previous day’s unwarranted go-slow.

We pitched up 400m from the end of the last stretch of cobbles, the Bernard Hinault section just 10 kilometres from the finish line. The atmosphere as the race came past was electric as the riders emerged through the thick clouds of dust that were spewed in to the air by the cars and motorbikes that rattled past.

Watching Cancellara thundering by, Andy Schleck doing the ride of his life to put time in to his rivals where no one expected him too, the world champion Cadel Evans in the thick of it, and Geraint Thomas showing the world the ability that his British Cycling and Team Sky coaches have known he has for a long time, made for a memorable moment.

Picking the rest of the riders out as they came through was a challenge. We’d been given some information over the phone, but with the field in countless small groups it was hard for anyone to know exactly what was going on.

We spotted Wiggins, brilliantly placed in the second big group, we missed Contador, but saw Vinokourov. Then we waited. Where was Armstrong? The seconds ticked by until a roar travelled down the crowd towards us. Suddenly there he was, riding down the gutter, squirming on top of his bike to keep it in a straight line and spinning too small a gear.

But he wasn’t on a charge, he was struggling in the gutter and looked bad. And he was on his own going backwards. Years of dominating this race, and a solid third last year have made him look near invincible. Today he looked very ordinary. Maybe he’s too old, or maybe he has other things on his mind.

As the race past us by over the next 20 minutes we heard the news that Thomas had placed second. Second on a Tour de France stage is good enough, but doing it on a stage that ripped the field to pieces is incredible. Not that ‘G’ doesn’t have form here. The Welshman won junior Paris-Roubaix back in 2004 and was 64th in this year’s senior event.

Long ago Dave Brailsford told me that Geraint was much better than even he realised, while on Sunday morning Rod Ellingworth, the man who brought Thomas through the BC academy system, said Thomas had been told there was to be no more talk of ‘potential’, and that now he had to start delivering.

Fifth in the prologue, second today, second on GC and leading the young rider competition is a pretty good delivery.

The race itself is now wide open. Andy Schleck is in a great position after putting time in to his rivals when no one expected him to, Contador has to attack, Wiggins and Evans are right back in the thick of things, and Armstrong looks like he’s swimming against the tide.

A stage such as this, when the unexpected happens, is just what the Tour needed. After years of formulaic victories played out over predictable routes, the race has sprung to life on a day that the fans enjoyed as much as anyone. And we were right in the thick of it.