Ireland's Dan Martin has won the sixth stage of the Tour de France, with Australia's Richie Porte closing on the top 10 after a day where several top names lost time on the leaders.
The Team UAE Emirates rider jumped away from the main pack inside the final kilometre and never looked back, beating France's Pierre Latour by one second and Spain's Alejandro Valverde by three.
BMC rider Porte, Italian Vincenzo Nibali and Britain's Geraint Thomas all crossed the line three seconds off the pace after the 181-kilometre ride from Brest to Mur de Bretagne, with defending champion Chris Froome five seconds further back.
Porte sits in 11th spot on the general classification 53 seconds behind his teammate, Belgian Greg van Avermaet, who is clinging on to the yellow jersey, three seconds ahead of Team Sky's Thomas.
Thomas picked up two bonus seconds during the stage, and left Froome in his wake on the final climb as he rode away from the reigning champion with a group of the other favourites.
The Welshman has been given free reign by Team Sky in the first week to race with Froome for the yellow jersey, although will be expected to revert to the role of super-domestique after the first rest day after stage nine.
Van Avermaet is the first former Olympic road race champion to wear the yellow jersey after winning gold since 1903 and has set a target to retain the jersey until the peloton reaches Roubaix on stage nine, which will be the next stage that could provide a general classification shake up.
Last year's runner-up Rigoberto Uran was 11 seconds behind Martin but it was worse for French hope Romain Bardet, who ended up 31 seconds off the pace after having to swap bikes with a teammate following a mechanical problem just before the last climb.
Dutchman Tom Dumoulin, the 2017 Giro d'Italia champion, suffered a puncture with five kilometres to go and ended the day 53 seconds behind the winner.
He was then handed a 20-second penalty by the race jury for staying too long in his team car's slipstream.
Martin came home second the last time a Tour stage ended in Mur de Bretagne three years ago and he admitted he had been obsessed about winning here this time on a punchy climb that suited his abilities.
"I thought about it (his second place in 2015) all day. It was good to finish second back then but this time I was coming for victory," Martin said.
"It was difficult because there was a headwind, so going solo was risky."
Martin becomes just the third Irish rider to win two or more stages on the Tour alongside Ireland's cycling royalty Sean Kelly and Stephen Roche.
It was in 2011 when the Tour first finished a stage on the steep, two-kilometre climb to Mur-de-Bretagne.
On that occasion Australian Cadel Evans laid down a marker on his rivals as he claimed the stage on his way to the overall win in Paris.
Friday will see the riders take on the longest stage of the race at 218km when they take off from Fougeres and finish in Chartres.
The last time this route was used was in 2004 and won by Australia's Stuart O'Grady from a breakaway.
This year the stage will be expected to finish in another bunch sprint, but the potential for strong winds to form could further impact the general classification if teams are not switched on.