PARIS, July 25 (Xinhua) -- Colombian riders grabbed the spotlight in Thursday's stage 18 as Nairo Quintana posted his third stage win and Egan Bernal became yellow jersey Julian Alaphilippe's closest rival in overall standings to kick off three consecutive mountain stages in the Alps that can well decide riders' fate in Tour de France.

In the 208km stage from Embrun to Valloire, Quintana rode away solo from the breakaway with 7.5km remaining from Col du Galibier, the final climb point of the stage, to another stage win in career after 2013 and 2018.

"Towards the finale, people started struggling and I felt I was in good shape. I waited for the right moment to make my move," said Quintana.

Leading main contenders, including Alaphilippe and Geraint Thomas, by over five minutes, Quintana moves up to seventh overall.

"Now in the Alps, I find climbs that I prefer due to the altitude," the Colombian stage winner added.

Fuelled by strong performance of the day, the 22-year-old Bernal also climbs from fifth to second in overall standings, replacing his Ineos teammate Thomas and trailing Alaphilippe by one and a half minutes.

"It's a very nice day for Colombia," said Bernal. "We have two very hard days ahead of us. We have to remain calm and not lose our focus because of today's joy. Let's keep our feet on the ground."

Thomas sits third overall with five seconds further behind, and is followed by Steven Kruijswijk and Thibaut Pinot.

Frenchman Romain Bardet became the second rider to have crossed the finish line on Thursday, 1 minute and 35 seconds adrift Quintana.

Living below expectation within the first two weeks, Bardet grabbed the polka dot jersey representing the best climber from Belgium's Tim Wellens.

"To defend the polka dot jersey is the only goal I have for the remaining of this Tour," admitted Bardet.

Departing from Saint-Jean-de-Maurienne on Friday, riders face huge challenges in the 126.5km stage to Tignes, with the summit of an HC climb point reaching as high as almost 2,800 meters.