Jumbo Visma News
The 23-year-old Frenchman Champoussin only turned professional a year ago, and with this first win, he raised a solitary finger in celebration before thumping his chest at the finish line.
The powerful 26-year-old, who won the Milan-San Remo and Strade Bianche classics in 2020, came second in this year's Tirreno-Adriatico and has emerged as a major force in the sport.
Defending champion Primoz Roglic pulled level with the same overall time as Carapaz. The Jumbo-Visma leader started the stage 13 seconds behind Carapaz, who rides for Ineos.
Roglic produced his trademark late kick in the final 500m to open a gap of just a few seconds for a comfortable win that puts him in the race leader's red jersey.
Last year's winner Bernal dropped off the lead group on the long Grand Colombier climb and appeared to lose his chance of retaining the title as he dropped to 13th overall, 8 minutes 25 seconds off the yellow jersey.
Dutch newspaper Telegraaf said Dumoulin, ambitious to trade up his second place for overall victory in the 2020 Tour de France, would ride for the Jumbo-Visma team for the next three seasons
Tour de France 2019: Egan Bernal sees lead trimmed by three seconds after mix-up in timekeeping during abandoned Stage 19
After climbing beyond his rivals in solo attacks on two consecutive Alpine stages, Bernal needs only survive a third one to seal victory in the 2019 Tour de France