There are widespread reports that the France and Fiji clash will be postponed due to a Covid-19 outbreak in the Fijian camp.
Organisers said on Thursday that they “do not envisage a cancellation at this time” but a significant increase in positive cases would force their hand.
However, France have cancelled their news conference, during which coach Fabien Galthie was due to announce the team to face Fiji in Vannes.
The French federation said the news conference was cancelled "due to exceptional circumstances".
Fiji rugby said earlier on Friday that one of their players had tested positive for the novel coronavirus.
Autumn Nations Cup: What happens if matches are cancelled?
With no room in the schedule for the match to be rearranged it would have to be scratched if it cannot go ahead on Sunday.
The game will be counted as a 0-0 draw, similar to what happened during the 2019 Rugby World Cup.
The tournament rulebook states: “Where a pool match cannot be commenced on the day in which it is scheduled, it shall not be postponed to the following day, and shall be considered as cancelled."
JOIN THE RUCK:
Meet the biggest and strongest beasts of the Autumn Nations Cup
1.Sam Underhill (England)
The flanker has a terminator like physique, but not only is he in great shape, he's also studying Politics and Economics at the University of Bath. Superman on the pitch, and a gentle giant off it.
2.George North (Wales)
Another Welshman known for bulldozing his way through defences, North has made his name by being monstrously strong. His sheer strength was most notably demonstrated on the 2013 Lions tour to Australia when he picked up Israel Folau and carried him… while the ball was in his hand!
SPT_GCK_280613_British and Irish Lions Tour 2013, Australia, Melbourne. Picture Graham Chadwick. George North and the Lions team take a dip in the sea at St Kilda
3. Andrew Porter (Ireland)
Height: 6′ 0″ Weight: 269 lbs
The powerhouse, who is renowned for his freakish ability in the gym, is poised to make a sizeable impact in this Autumn Nations Cup. At just 20, he could squat 280 kilograms. It's anyone's guess what that number is now. The story goes that they literally ran out of weights for him to lift back in school such was (and is) his freakish strength. A name to look out for.
4.Leigh Halfpenny
The Wales fullback isn’t the biggest on the list, not by a long shot. Halfpenny has put on some serious size over the years and is a solid unit on the field. He has a great shape and very lean, women’s choice it seems!
5. Jamie Bhatti (Scotland)
He built his solid frame outside the conventional confines of the gym. Bhatti spent his youth lugging around cow carcasses as part of his job as a slaughterman.