Geraint Thomas will wear the yellow jersey after winning stage 11 of the Tour de France in La Rosiere to take the overall lead.
Thomas attacked six kilometres from the top of the final climb of this 108.5km stage from Albertville, overhauling rival Tom Dumoulin and then pushing on to catch former team-mate Mikel Nieve who was looking to win the stage out of the breakaway.
It will be a second spell in yellow for Thomas, who won the opening time trial of last year's Tour in Dusseldorf.
Ireland's Dan Martin came in 27 seconds behind the winner in sixth place, and moves up to tenth in general classification.
The UAE Team Emirates rider is now 3' 16" behind the leader.
Thomas' Sky team-mate Chris Froome was third on the stage, level on time with Team Sunweb's Dumoulin as they came home 20 seconds after Thomas.
That sees Froome move up to second in the general classification, with the provisional standings showing him one minute and 25 seconds behind.
Dumoulin now sits third, a further 19 seconds back.
Thomas' second career Tour stage win was delivered with panache.
Though the sight of Sky massed on the front of the peloton most of the day was not one to excite fans, the way in which he attacked with yellow on the line was.
With BMC's Greg Van Avermaet struggling off the back of the peloton by the midpoint of the stage on the Col du Pre, the battle for yellow was on.
Movistar's Alejandro Valverde tried a long-range attack, while Dumoulin attacked on the descent of the penultimate climb, the Cormet de Roseland, linking up with Valverde before the road rose up again towards La Rosiere.
But Sky kept their powder dry until Thomas launched his move. Froome initially held back, marking counter-moves from AG2R La Mondiale's Romain Bardet and Martin before leaving them both behind.
By catching Dumoulin, Thomas had already done enough for yellow but wanted more as Nieve slid into view, kicking again to pass Nieve inside the final 400 metres and take the stage win.
But while Team Sky could celebrate, Team Dimension Data did not get the Mandela Day gift they were hoping for as Mark Cavendish faced elimination from the Tour, missing the time cut after being dropped early on and spending the entire stage off the back.
Thomas said: "It's unreal, I didn't expect it at all. We were low on numbers so it was more instinct when I went so we didn't get caught having to ride.
"I had a little gap and then obviously Froomey could follow the guys then. I committed to go over to Dumoulin and then I could just sit in as Froomey came across.
"I could see Frosty (Nieve), he's a good mate so it's a shame but I had to go for that win, it's super nice."
Asked about yellow, he added: "I knew it was a good chance but I didn't know how everybody else was going to ride. To wear the yellow jersey is always a massive honour. I managed to do it last year but to do it two years on the trot is really nice."