After an agreement between the Rugby Football Union and Premiership Rugby dictated that Eddie Jones was only able to select 28 players for the Six Nations, owing to the fact that his squad will need to be in a ‘bubble’ away from their clubs for the duration of the championship, the England head coach also selected a 12-man “shadow squad”. This dozen-strong group will remain at their clubs throughout the tournament, but they will be subject to the same testing regimen as the 28-man cohort. Meaning that, if anyone was to drop out, someone from the shadows will be healthy and ready enough to immediately take his place. Here, Telegraph Sport runs through the 12. Charlie Atkinson (Wasps, uncapped) Young fly-half whose precocious temperament has been evident in several of Wasps’ punchy displays this season, notably in victories over Montpellier and Sale. The 19 year-old might have to bide his time for an appearance, however, as his club mate, Jacob Umaga, is seemingly ahead of him in the pecking order. One to watch. Ali Crossdale (Saracens, uncapped) The Saracens wing is one of the most unknown names among the 12. The 22 year-old has featured for England age-group sides, but he has not played since Saracens’ away loss to Worcester at the end of September. When you add in that he is uncapped, any inclusion in the next two months would be a shock. Tom Dunn (Bath, three caps) The Bath hooker can count himself as one of the unluckiest to miss out on the squad; the restricted squad size available to Jones meant that carrying three hookers would have been foolhardy and in Jamie George and Luke Cowan-Dickie Jones has two of Europe’s best. If there is an injury to one of the aforementioned duo, then he will definitely feature. Charlie Ewels (Bath, 17 caps) Ewels makes way for Courtney Lawes, with the Saints lock returning after missing the autumn campaign through injury. As the most senior lock among the shadowing dozen, however, the understated 25 year-old is fairly likely to be promoted to the senior squad at some stage across the championship, even if he does not feature on matchday. George Furbank (Northampton, three caps) The full-back’s chances with England have been limited since he made his debut in the Six Nations loss in Paris last year, on the back of some glitzy, class-oozing displays for the Saints. The 24 year-old was recalled into England’s training squads for the Autumn Nations Cup, but he is often unfairly maligned due to that day in Paris. If Elliot Daly is crocked, Furbank could see a recall. Joe Heyes (Leicester, uncapped) Tigers’ tighthead was called up to the squad for that ill-fated match against the Barbarians in the autumn after showing some bite for his club, albeit off the bench. But the 21 year-old’s reputation is such that, with Kyle Sinckler’s ban, the former Nottingham Forest youth goalkeeper is third choice. An injury to Will Stuart or Harry Williams in the next fortnight and he could make his debut. Jonathan Joseph (Bath, 54 caps) England are well aware of what the British and Irish Lions centre can offer, but the thunderous rise of Paolo Odogwu, coupled with the restricted squad numbers, has resulted in the centre-cum-wing’s omission, despite his versatility. The 29 year-old’s form with Bath has not been setting the Premiership alight, either, but his experience and versatility mean a call-up is likely. Joe Marchant (Harlequins, four caps) Marchant has shown glimpses of his talent for Harlequins this season, but the general malaise at his club – particularly in generating go-forward – has limited the 24 year-old’s space in the midfield, which is vital for his pacey approach. Playing a similar centre/wing role to Joseph, who was above Marchant in the pecking order in the autumn, an appearance for the Quin is unlikely. George Martin (Leicester, uncapped) Despite making only a handful of appearances for the Tigers, the second row has slotted seamlessly into Premiership action like a seasoned journeyman. A club insider has described the 19 year-old as Leicester’s “best second-row prospect since Martin Johnson”, words with enough gravitas to entice Eddie Jones. Although Ewels is more likely to feature in the coming months, Martin’s stock is rising. Alex Mitchell (Northampton, uncapped) Mitchell was seen as the next big thing when he was first called into the senior squad as an apprentice at the start of the 2020 Six Nations, but since then the 23 year-old has not made the No 9 jersey his own with Saints and has been usurped in the senior squad by fellow tyro Harry Randall. With Dan Robson and incumbent Ben Youngs also in the senior squad, Mitchell’s opportunities will be limited. Jacob Umaga (Wasps, uncapped) Unfortunately for Umaga, he has both the immaculate George Ford and, most likely, the England captain Owen Farrell ahead of him in the pecking order for the fly-half jersey. That will not stop the 22 year-old, though, from continuing to impress with his mature control and footballing ability at his club. Son of Mike and nephew of Tana, he will surely be playing international rugby sooner rather than later. Jack Willis (Wasps, two caps) Wasps’ turnover supremo has been obscenely unlucky in missing out for this year’s Championship, especially considering there has been not even the slightest sign of second-season syndrome after his 2020 debut. But England’s back-row depth is embarrassingly rich and selection must have been tight; regardless, if any second or back row is ruled out, Willis will surely be the first man for whom they send.