Geraint Thomas of Great Britain and Team Sky Yellow Leader Jersey / Celebration / during the 105th Tour de France 2018, Stage 12 a 175,5km stage from Bourg-Saint-Maurice Les Arcs to Alpe d'Huez 1850m / TDF / on July 19, 2018 in Alpe d'Huez, France.
Welshman Thomas, of Team Sky, took the lead of the race on Wednesday with victory atop La Rosiere on what was the second day in the Alps.
The Team Sky rider finished two seconds ahead of fellow General Classification contender Tom Dumoulin and three and four clear, respectively, of Romain Bardet and teammate Chris Froome, who was again the target of negative attention from spectators.
In the end, Van Avermaet produced a fantastic performance to finish 1min 43secs behind Alaphilippe, Thomas, Froome and Team Sky trailing over the finish over three minutes behind the stage victor.
"To win the stage is unbelievable, certainly one of the best days of my career, so now I'm going to enjoy the day tomorrow".
"Unbelievable. Not in my wildest dreams did I ever think I would win up here, " Thomas said.
Thomas broke from his Team Sky teammates with 5.5 km to go, with teammate and 2017 Tour de France victor Chris Froome following in pursuit. "When Froome attacked I went after him and felt good".
Nowhere do the crowds get more up close and personal than they do here, and Froome was slapped by one spectator on the final climb and appeared to be spat at by another.
"He should have been fighting for victory, " Thomas said of Nibali.More news: MGM Resorts Sue Las Vegas Shooting Victims, Denying Liability
"I'm speechless", said Thomas.
With bonus seconds applied, Thomas extended his lead in yellow over Froome by 14 seconds to one minute 39 seconds, but insisted the four-time Tour victor remained Team Sky's leader in the race.
But the second of three days in the French Alps proved a step too far for the Isle of Man sprinter, who has amassed an impressive 30 stage wins in 10 previous editions.
Sprinting standout Mark Cavendish, meanwhile, finished far behind and missed the time limit, ending his Tour.
Thomas, who wore the yellow jersey for four days in 2017 after winning the opening time trial, now leads teammate Froome by 1min 25sec in the overall standings.
Last year's runner-up Rigoberto Uran abandoned the race prior to the start of the stage after failing to recover from injuries sustained in a crash on Sunday.
And for a long while, it looked like Thomas's lead was in danger when Dutchman Steven Kruijswijk launched an audacious attack after he had squeezed into an early breakaway.