Eddie Jones' scope to surprise when he names England's Guinness Six Nations squad from self-isolation has been severely restricted, but Wasps finisher Paolo Odogwu could feature as a bolter.
Jones has been forced to finalise selection for his team's title defence from home after his assistant Matt Proudfoot, who oversees the forwards, tested positive for coronavirus.
England's head coach still names his squad late on Friday afternoon as planned knowing that having been limited to 28 players for the duration of the tournament, his scope for experimentation has been eroded.
The reduction from the customary number of around 32-36 is to help minimise the potential for an outbreak of Covid-19 by curtailing movement in and out of the bubble environments at St George's Park and the Lensbury, their bases over the coming weeks.
An advantage of the new system is that Jones is able to retain the 28 for the entire week rather than being required to send some players back to their clubs on Tuesday night.
It means there is no room for bringing apprentice players into camp, with Harlequins fly-half Marcus Smith and versatile Wasps forward Alfie Barbeary, who is recovering from ankle surgery, recent examples.
The squad will have a familiar look as Jones retains the players who served him well during a triumphant 2020 when the Six Nations and Autumn Nations Cups titles were secured in quick succession.
But the Australian has had his eye on Odogwu, who has emerged as a devastating force at centre and wing for Wasps this season, topping the stats charts for clean line breaks and most metres made.
The uncapped 23-year-old of Nigerian heritage can also represent Italy through his father, so picking him would be a step towards securing his Red Rose allegiance.
Jones will have to consider the demands of the coming weeks carefully knowing that, barring injury, he must work with the same players for the entire tournament, which begins against Scotland at Twickenham on February 6.
There are various permutations in the second and back rows, with the return to fitness of Courtney Lawes after the Northampton forward sat out the autumn with an ankle injury offering an option at lock and blindside flanker.
If Jones opts for a fifth back row player, Jack Willis of Wasps would be favourite, while Jonny Hill of Exeter should make the cut as the fourth lock.
A complication in the pack is tighthead prop with Kyle Sinckler set to miss the Scotland opener through suspension.
If Jones decides he needs specialist cover, he will have to break with tradition and pick a third player, with Exeter's Harry Williams thereby in line for inclusion.
However, Joe Marler was regarded as an option in the position in the build-up to the 2019 World Cup.
Also complicating matters is the outbreak of coronavirus at Bath that has forced all players and staff at the club to self-isolate while the training ground undergoes deep cleaning.
Anthony Watson, Will Stuart and Charlie Ewels could be delayed in joining up with England at St George's Park next week unless cleared by the next round of testing.
