He will need to be at the top of his form on Thursday for the start of an Alpine trilogy of stages including six climbs over 2,000 meters. This is when the race — the most exciting in the last decade — will be decided before Sunday’s ceremonial ride to Paris.

Sixteen stages of 21 have been completed, but the suspense remains intact, with six riders separated by little more than two minutes. Behind Alaphilippe and Thomas, Steven Kruijswijk remained third, 1:47 off the pace and three seconds ahead of Thibaut Pinot. Thomas’s Ineos teammate Egan Bernal lags 2:02 behind, and Emanuel Buchmann has a 2:14 deficit.

Bernal, a Colombian and one of the best pure climbers in the Tour, played down Thomas’s crash and said the race in the Alps would suit him more than the Pyrenees, where both Ineos leaders conceded time to Pinot.

“He crashed but with no consequence, and I don’t think he’ll suffer from it in the coming days,” Bernal said. “We’re approaching the Alps. The climbs there are longer and steeper. They’re more of the Colombian style of climbing. I’m ready and I feel good.”

Ewan said he suffered from the heat throughout the stage — temperatures soared as high as 40 degrees Celsius, or about 104 degrees Fahrenheit — but it did not slow him down in the finale. A Tour rookie, he edged Elia Viviani and Dylan Groenewegen to post his second stage win after his maiden success in Toulouse last week.

Earlier, riders tried to cool down with bottles of cold water against the backs of their necks as they pedaled on the Pont du Gard, an ancient Roman aqueduct bridge set against a dramatic landscape of rocks, trees and water. Alexis Gougeard, Lukasz Wisniowski, Stéphane Rossetto, Paul Ourselin and Lars Bak organized the day’s breakaway and had a maximum lead of two minutes.

After the group was caught two kilometers from the finish, Viviani was set up by his teammates and launched the sprint about 200 meters from the line but could not resist Ewan’s comeback.

“To be honest, I felt so bad today during the day,” Ewan said. “I think the heat really got to me. I was really suffering, but I had extra motivation today because my daughter and wife are here. I’m so happy I could win for them.”