The 156 km (97 mile) stage started and ended in the largest city on the French Riviera, but unusual conditions with persistent rains saw a number of top contenders hit the tarmac in deadly falls.
Kristoff was one of the victims but benefited from a “truce” declared by the leading riders of the peloton, which slowed considerably for safety reasons, allowing accident victims to catch up and compete for the finish.
It was only in the final stages that the race resumed for good, although another mass crash just under 3 km (2 miles) from the end, left house favorite Thibaut Pinot among the victims, the Frenchman getting up to complete the stage without serious injury. .
UEA Team Emirates rider Kristoff used his experience in the final gust to win honors from world champion Mads Pedersen of Denmark and Dutch rider Cees Bol. Seven-time green jersey winner Peter Sagan finished fifth on the scoreboard for the line.
Defending champion Egan Bernal of Colombia finished safely in the peloton, but one of his main support riders from Team Ineos, Pavel Sivakov, lost twice.
Bernal’s compatriot, Astana captain Miguel Angel Lopez suffered a particularly severe fall on a descent that saw him slam his head first into a traffic sign.
One of the other favorites of the race, Slovenian Primoz Roglic finished alongside Bernal, the Jumbo-Visma rider summing up the peloton’s mood on day one of a three-week race.
“We all just didn’t want to do stupid things. You can still have a race and a sprint, but no one was planning to crash on the first day, ”he told ITV 4.
Roglic, who has shown impressive form in the warm-up races, is expected to make his mark on Sunday’s 186km (115 mile) stage, starting and finishing again in Nice, but with two climbs majors to test the legs of the contenders. for the general classification.
The tour was originally scheduled to start at the end of June, but like most major sporting events, has been postponed due to the coronavirus pandemic.
It takes place with strict health protocols in place, with teams facing deportation if two or more members of their entourage, including runners and support staff, test positive for Covid-19.
Fans, who normally race the roadsides, especially on major climbs, face heavy restrictions and only 100 spectators were allowed to enter the finish area on the Promenade des Anglais on Saturday.
With the increase in Covid-19 infections in France, there has been speculation that the Tour may not even reach its traditional finish in Paris, but French Sports and Education Minister Jean-Michel Blanquer has gave an optimistic message.
“You cannot rule out the cancellation of the Tour, but it has been so well prepared that the chances of that happening are very low,” Agence France-Presse quoted at the start line on Saturday.