After his Australian BMC teammate Richie Porte crashed out of the Tour on Sunday, Van Avermaet started the second week with no agenda but to stay in yellow as long as he could, and put in a ride to honour the jersey. "It meant Froomey could follow behind so ideal scenario really". "If I have to pull towards the end, then I will", Thomas said.
Thomas dons the yellow jersey for a second straight Tour.
Froome punctured on the gravel, however, and found himself at the back of the bunch as it passed the Tour's tribute to World War Two's Maquis de Glieres resistance group.
The selection, as is often the case on the Tour's first mountain stage, came at the rear of the group, where Rigoberto Uran (EF Education First-Drapac) and Ilnur Zakarin (Katusha-Alpecin) were among those distanced.
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. On Tuesday, he even entertained the notion of attacking, but Team Sky's brisk pace-making on the Col de Romme and the Col de la Colombière - not to mention the block headwind - quickly dispelled the idea.
Thomas, who is from Wales, required slightly less than 3 1/2 hours to complete the 108.5-kilometer (67-mile) route from 1992 Winter Olympics host city Albertville to La Rosiere Espace San Bernardo ski station.
The terrain was very different, but the first day of the second part of the 2018 Tour de France proved to be rather like the days that preceded it. He wore the yellow jersey for four days a year ago - before dropping to second behind Froome - then crashed out on a descent in Stage 9. Asked whether his performance, and his claiming of the yellow jersey, had changed anything with respect to leadership duties at Team Sky, Thomas was unequivocal.
The first overall contender to attack was Alejandro Valverde up the Col du Pre. I committed, got across to Dumoulin and then sat on.
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.