BRIANCON, France -- Speeding downhill at 75 kph (45 mph) on unprotected Alpine roads, Tour de France rookie Primoz Roglic scaled the race's highest peak and then barrelled down the other side while holding off the competition on the famed Galibier climb to win Stage 17 on Wednesday.

Chris Froome consolidated his overall lead as Fabio Aru lost touch with the three-time champion's group on the punishing gradients of the Galibier. The mountain pass rises to 2,642 metres (8,668 feet) in altitude, with the thinning air compounding the effort for the riders.

Froome finished 1 minute and 13 seconds after Roglic in a group with Rigoberto Uran and Romain Bardet, who climbed to second and third overall respectively. Aru dropped from second to fourth.

Determined not to give any ground, Froome outsprinted Bardet to the finish line, securing four bonus seconds for placing third on the stage. Uran was quicker still, beating Froome to get six bonus seconds for second place.

Aru couldn't keep up with Froome's group on the Galibier, falling behind after the bursts of acceleration from Bardet and Irish rider Dan Martin. Mouth open, the Sicilian repeatedly laboured his way back to the group until a final burst of speed toward the top from Bardet dropped Aru for good.

Bardet said he was hoping to leave Froome behind, too. But the Briton showed no signs of difficulty in staying with him on a stage that moved him a big step closer to keeping the yellow jersey all the way to Paris.

"I did my utmost," Bardet said. "I raced to take the jersey and I came close to dropping them at the top of the Galibier. I attacked. That's the way I love to race. I have no regrets. I tried everything."

Bardet, Froome, Uran, French rider Warren Barguil and Mikel Landa zoomed down the long descent from the top together, never slowing, to prevent Aru from catching them.

Aru is now 53 seconds behind Froome overall. Uran and Bardet trail the leader by 27 seconds.

"It was a big day of climbing," Froome said. "My legs certainly felt a lot better than a week ago in the Pyrenees, which is a good sign."

The Team Sky leader was greeted at the finish by French President Emmanuel Macron, who followed the stage in a car with the race director.

Another tough day of climbing awaits Thursday, with a mountain-top finish on the Col d'Izoard. If the overall standings remain as close as they are now, the final time trial on Saturday could be decisive in determining the podium places at the finish in Paris the next day.

"At this stage of the race, everyone's on their hands and knees, let's see what happens," Froome said. "It's still all to race for."

Roglic, a former ski jumper, is the first Slovenian to win a stage in the 114-year history of the Tour.

The Team Lotto rider sped away from his own four-man group, which included two-time champion Alberto Contador, with five kilometres (three miles) still left to climb on the Galibier. He laboured to the top, through barren slopes of scree and patchy grass, and then raced down alone over the last 28 kilometres (17 miles) to the finish at the Serre Chevalier ski station.

"It's unbelievable," Roglic said. "A really crazy stage."

The Tour lost Marcel Kittel, the winner of five stages this year, after he crashed in the first of four ascents on the 183-kilometre (114-mile) stage from La Mure. With blood running down his right leg and his shoe apparently broken, Kittel pulled up.

With a new a new bike and a new shoe, he got going again and was treated while he rode by the Tour's doctor. But the German later abandoned.

Kittel had been leading the Tour's green jersey competition, awarded for points collected in sprints during and at the end of stages. He had 373 points. With his departure, Australian Michael Matthews inherits the jersey. He has 364 points.

One of the most active riders Wednesday was two-time champion Alberto Contador. Riding with the panache of his glory days, the 35-year-old Spaniard sped away from Froome's group on the second and longest climb, the 24-kilometre (15-mile) ascent to the col de la Croix-de-Fer. But Contador faded in the Galibier and could not stay with Roglic.

"I want people to remember me as a rider who tried things, who was courageous," Contador said.