Alex Dowsett soloed to victory in the Giro d'Italia eighth stage on Saturday to give his Israel Start-up Nation team a first win but fellow Briton Simon Yates' exit hours earlier after a positive coronavirus test has left the race on edge.
Yates, 28, withdrew before the start of the 200km stage from Giovinazzo in Puglia to Vieste after becoming the first rider to test positive for Covid-19 at a Grand Tour.
The Mitchelton-Scott team leader, who won the Vuelta in 2018, was 21st in the standings ahead of Saturday's stage with overall victory still potentially within his grasp.
"Simon's health remains our main concern and, thankfully, his symptoms remain very mild and he is otherwise in good health," team doctor Matteo Beltemacchi said.
Yates tested positive after developing a slight fever on Friday, and a second test confirmed the positive result.
But questions remain about how he caught the virus and whether he passed it on to others as his teammates were all cleared to continue the race.
"Yates is the first case after ten days," said Giro race director Mauro Vegni.
"This means that the 'bubble' at the Giro held up very well, quick checks allowed us to promptly ascertain Yates' positivity.
"If we had only followed the International Cycling Union protocol, we would certainly have lost precious time, we would have been forced to send the swabs to Milan and then wait for the result tomorrow (Sunday).
"Today, therefore, Yates would have left to compete in the stage, risking to infect other riders."
- 'New checks'-
Vegni said that riders from a dozen teams would now undergo fresh swabs on Sunday with the first rest day on Monday.
"On Monday morning, thanks to a reinforced team, we will complete the samples and send them to Milan," he continued.
"We will wait for the results before the start of the stage on Tuesday and on Wednesday we will carry out new checks on everyone."
But the future of the three-week Giro remains linked to the outcome of the next round of tests.
"We all want to get to Milan, only a possible intervention by the authorities could stop us," added Vegni of the race finish on October 25.
Yates retirement after fellow Briton Geraint Thomas and Colombian Miguel Angel Lopez has now deprived the race of three top contenders.
Two-time winner Vincenzo Nibali's hopes have been boosted with the Italian sixth overall, one-minute behind Portugal's Joao Almeida, who holds the leader's pink jersey.
In Vieste, Dowsett produced a powerful finish to cross the line alone more than a minute ahead of Italian Salvatore Puccio of Ineos and Briton Matthew Holmes of WorldTeam Lotto.
Dowsett shook off his five breakaway companions with 20km to go, with the former world Hour Record holder finishing as in a time trial.
- No contract, baby on way -
The 32-year-old rider from Essex claimed his second Giro stage win, seven years after his first.
"I can't say how much I needed a win like this in such a difficult year," said Dowsett.
"Since Israel Start-Up Nation stepped up to the WorldTour, we’ve been fighting for this victory."
He added: "I don't have a contract yet for next year and with a baby coming in January, I really needed such a result so badly, I cannot believe it."
Deceuninck's Almeida finished 17th nearly 14 minutes behind Dowsett to lead Spaniard Pello Bilbao (Bahrain-McLaren) and Dutch rider Wilco Keldermann of Team Sunweb going into Sunday's ninth stage over 208km from San Salvo to Roccaraso.
"Tomorrow will be a crucial day for the defence of the Maglia Rosa," said Almeida. "My whole team has worked so hard for this jersey up to now, we won’t let it go."
The mountainous stage in Abruzzo finishes at altitude with a final climb of 9.6km.