This year's Giro d'Italia has been robbed of its most challenging climb as organisers told AFP on Tuesday that there is too much snow covering the Great-Saint-Bernard Pass.
The cyclists were due to tackle the 2,469 metres mount on Friday's 13th stage but instead will ride through the tunnel which is 600 metres lower down on the way to the finish in the Swiss municipality of Crans-Montana.
The 2 304m Tre Cime di Lavaredo – where the 19th stage reaches a climax on May 26 – takes over the mantle of 'Cima Coppi' (named in honour of the legendary five-time champion Fausto Coppi) as the highest climb of this year's edition.
The Giro's scheduling in May makes it especially vulnerable to the variable moods of the weather.
The heavy snowfalls in the Alps in recent days will make the third and final week of the race particularly challenging as it is dominated by climbs.
The penultimate stage could be of special concern to race chiefs – a time-trial on a narrow road climbing to a finish at Monte Lussari some 1 766 metres high.
This comes as a second blow in a matter of days for Giro organisers with overall leader and race favourite Remco Evenepoel withdrawing on Sunday due to a positive test for Covid.
The Belgian was not obliged to withdraw due to a positive test – it is at the team's discretion whether a rider carries on or not as the Covid health protocol has been dropped.
Others, though, followed suit in pulling out on Tuesday due to Covid – Italian Domenico Pozzovivo and his Israel PT teammate Mads Wurtz, even though the latter tested negative he did not feel well enough to continue.
Intermarche's Norwegian rider Sven Erik Bystrom also failed to make the start line for the 10th stage as although cleared by the International Cycling Union's (UCI) medical staff he developed further symptoms overnight.
"He was withdrawn as a precautionary measure, and with the desire to care for his health," said the team.
Race organisers had taken extra measures on Monday to prevent the field being further decimated by the spread of the virus.
"In the light of the latest developments concerning positive test results on some riders, the direction of the Giro d'Italia informs that wearing a facemask will be compulsory in all areas of contact with the riders," said a race statement.
The statement said those areas include team buses and areas it supervises at the start and finish of each stage.
Those still involved will take on a 196km ride from Scandiano to Viareggio with Britain's 2018 Tour de France champion Geraint Thomas in the pink jersey.