After a late pile-up on Nice's iconic Promenade des Anglais, Alexander Kristoff of UAE Emirates won a crash-marred opening stage of the Tour de France on Saturday.

The Norwegian will now wear the overall race leader's yellow jersey, having fought back from an early fall that looked like ruling him out.

The 2020 Tour set off two months later than planned due to the coronavirus and under strict health protocols.

However, the first rain in the Mediterranean city since June turned the opening jaunt of the 21-day race into a lottery with one motorbike race official describing the road surface as an ice rink.

Key victims of the multiple crashes included French hopes Thibaut Pinot and Julian Alaphilippe, with Colombia's Astana captain Miguel Angel Lopez suffering a jaw-dropping downhill slide that saw him slam face-first into a traffic sign.

British team Ineos were left to fret over their Russian climber Pavel Sivakov, who fell twice, riding with both elbows bloodied.

Message Of Hope

Top riders, led by the Jumbo team, were shocked by the crash and a truce was called that slowed down the pace.

"That was great for me, allowed me to get right back in," said Kristoff, who had been around six minutes adrift after his own tumble.

"This is a special Tour, even I am surprised," said the 33-year-old who admitted his season's targets were the coming one-day races, Paris-Roubaix and the Tour of Flanders.

Along the final flat home straight the speed had risen to around 65 km/h when the fall left 30 or so riders ahead alone with dozens of startled contenders sprawled.

The heavy Covid-19 atmosphere weighing on the seaside city was lightened slightly at the start when French government minister Michel Blanquer sent out a rare message of hope the Tour would make it all the way to Paris in three weeks' time.

"You can't rule out the cancellation of the Tour, but it has been so well prepared that the possibilities of it happening are very slim," he said.

Prince Albert of Monaco played local game boules in the VIP village at the start line but the Italian style red-roofed city was eerily empty on the day, as fans had been asked to stay away, and even the pebbled Nice beach was semi-deserted.

Local paper Nice-Matin raised eyebrows on Saturday running a picture of the Dutch team Jumbo's leader Primoz Roglic, one of the favourites, instead of a Frenchman.

"A Good Night's Sleep" Needed

But the key Frenchmen in the race both had days to forget.

After 14 days in the lead last year Alaphilippe was forced to fight back alone from two minutes down after a mechanical issue.

Meanwhile, luckless fan favourite Pinot was involved in the last of many falls as the peloton swept along the rain-sodden seafront walkway.

"That's road racing," said Pinot's manager Marc Madiot. "Nothing a good night's sleep won't put right," he added after his star stormed back to the team bus refusing to speak.

Sunday's 186km stage also starts and ends in Nice but will be run under blue skies and over the Alps in the Nice back country.

"The Tour has never gone so high, so early," Tour chief Christian Prudhomme said of the two climbs of Colmiane and Turini, both over 1500m high just a few kilometres back from the beachfront walkways.

Burly yellow jersey Kristoff is too heavyset to have a hope of coming home with the favourites on Sunday.

"I guess I'll lose the jersey," he said. "But I'm near the end of my career and I've got four kids, so I'll just try and enjoy the day."