Gap, France - Britain's Geraint Thomas survived a terrifying crash on a hair-raising descent as Ruben Plaza won Monday's 16th stage of the Tour de France.
Chris Froome finished in an elite group of favourites to maintain his 3min 10sec lead over Nairo Quintana but his teammate Thomas came close to disaster on the 201km ride from Bourg-de-Peage to Gap.
Young Frenchman Warren Barguil lost control on a dangerous corner and bumped into Thomas who was knocked over a sheer drop, hitting his head on a lamppost as he went over the edge.
Incredibly, the tough Welshman climbed back onto the road and after a swift change of bikes, he carried on, losing less then 40 seconds by the finish.
"I'm OK, I just hit my head on a lamppost but I'm alright," said the chirpy 29-year-old.
Barguil blamed the crash on American Tejay Van Garderen, claiming the BMC man had bumped into him before he lost control.
A French TV commentator following on a motorbike said Thomas looked "groggy" but fine as he remounted.
That drama happened almost 20 minutes back from Spaniard Plaza's stage victory as the Sky-led peloton had shown no interest in chasing a 23-man breakaway.
Lampre's Plaza attacked with 18km left on the final climb -- an 8.9km-long second category ascension with an average gradient of 5.6 percent.
He crested the summit, 12km from the finish, with around a minute's gap to nine chasers as the breakaway group had splintered.
Peter Sagan led the chase and came home second at 30sec -- taking his fifth runners-up spot on a stage this year as his two-year wait for a Tour victory drags on.
Colombian Jarlinson Pantano was third at 36sec while Eritrean Daniel Teklehaimanot earnt his best finish at the Tour, finishing seventh.
Behind the breakaway, Van Garderen's BMC team had picked up the pace of the peloton coming into the final climb before Alberto Contador's Tinkoff-Saxo outfit pushed hard on the ascent.
Contador himself attacked near the top of the climb, but Froome managed to reel him back in, only for reigning champion Vincenzo Nibali to take the opportunity to accelerate away himself.
The Italian had eeked out a 15sec gap to the rest of the favourites at the top and by the finish he had snatched back a morale-boosting 28sec on what has otherwise been a disappointing defence of his title as he sits eighth overall.
Nibali, known for his daredevil descending, was clear of the drama behind him but Thomas showed great bravery in carrying on and only losing 38sec by the finish -- an incredible effort given he had to change bikes after clambering back up onto the road.
The big loser, though, was Frenchman Tony Gallopin, who started the day ninth but seemed to lose his bottle on the descent and lost several minutes to drop out of the top 10, with Barguil benefitting.
In the breakaway group, Australian Adam Hansen was the first to strike out for home inside the final 50km before Austrian champion Marco Haller caught him.
But they were both hauled back early on the final climb and after several tentative attacks, Plaza managed to make one stick.