Britain's Geraint Thomas wins stage one
Welshman clocks 16 minutes four seconds for 14km time trial
Team Sky team-mate Vasil Kiryienka is second
Defending champion Chris Froome sixth
GC contender Alejandro Valverde out after big crash
Geraint Thomas is on the podium ready to receive his first ever Tour de France yellow jersey.
That's my cue to head off and pick the bones out of that stage for the report, which is building here.
Phew. What a day. Hope you can join us when we do it all again tomorrow. Can Mark Cavendish make it back-to-back British stage wins?
For now, farewell.
GC contender Richie Porte, speaking on ITV4: "Keeping it rubber-side down was the goal. Before I went out, I followed Nicolas Roche in the car and he binned it so I was a little bit petrified. It was such a slippery course.
"I would have liked to be a bit quicker but wanted to keep all the skin in tact. I took no risks and that was the way to ride it."
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Geraint Thomas, speaking on ITV4: "It is unreal, it is the start of my eighth tour and it is my first stage win. I didn’t even dream of this last night. Wow, it is unbelievable, I am lost for words.
"I have a tendency to go out hard but I am getting older now and learning to pace myself. It couldn’t have gone any better."
Rob Hayles
Former GB cyclist on Radio 5 live sports extra
Absolutely incredible ride from Geraint Thomas, nobody saw that coming, not even the TV director!
Simon Brotherton
Radio 5 live sports extra commentator
It was set up for Tony Martin in front of his home crowd but Geraint Thomas has taken it from him in his back yard.
The yellow jersey will be on Thomas' shoulders tonight for the first time in his career. What a day for Team Sky and what a day for British cycling!
Image source, Getty ImagesDid anyone see this coming? The TV director didn't, having not bothered to follow Geraint Thomas for any part of his ride.
When they did pick him up, the Welshman was flying across the finish line in a belting time of 16 minutes four seconds, which proved enough for him to win his first ever grand tour stage.
Not a stage you'd have bet on him winning, even if he's always been a good time trial rider.
Thomas will be in yellow for the first time tonight. Team Sky have laid down yet another imposing marker.
He's not got it...Chris Froome comes home in 16 minutes 16 seconds - 12 seconds behind team-mate Geraint Thomas, who takes his maiden grand tour stage win.
That's a great time for Froome though, taking crucial seconds on his GC rivals.
The last rider on the road, the defending champion, Chris Froome is into the final stages...
Rob Hayles
Former GB cyclist on Radio 5 live sports extra
Chris Froome is riding to clockwork as it stands, comfortably ahead of Porte and Quintana.
His biggest rival at the moment in terms of general classification is teammate Geraint Thomas!
Nairo Quintana posts 16 minutes 52 seconds.
That's a very solid ride from the Colombian climber, not least having seen his team-mate Alejandro Valverde crash out.
Meanwhile, GC contender Fabio Aru has just posted 16 minutes 56 seconds.
Alberto Contador comes through in 65th place, just waiting for a confirmation on time.
Rob Hayles
Former GB cyclist on Radio 5 live sports extra
Geraint Thomas looks like he left a bit more in the tank for the end and he had the psychological advantage of having Romain Bardet right in front of him – he had a carrot to chase.
Stefan Kung cannot better Geraint Thomas either!
The Swiss BMC Racing Team rider comes home five seconds behind the Welshman.
Only Chris Froome can deny his team-mate the yellow jersey now and that's looking unlikely...
There remains a big threat to Geraint Thomas out there in the shape of Stefan Kung of BMC.
He was just one second off Tony Martin at the checkpoint.
Chris Froome has just gone through that checkpoint in nine minutes 28 seconds. That's five seconds off where Geraint Thomas was.
Ooo-er, slip for Nairo Quintana, but he just about keeps it upright.
The Colombian needs to stay upright and come in around the 17 minute mark to limit his losses.
Geraint Thomas effectively took 12 seconds on Tony Martin in the second half of this time trial.
Staggering.
Rob Hayles
Former GB cyclist on Radio 5 live sports extra
I’m speechless! Did Tony Martin take it too easy on the bends? Was Geraint Thomas too good? Probabaly a bit of both.