Still basking in the plaudits received after showing tremendous strength, resilience and defensive fortitude to beat weary Argentina 27-14 in their penultimate autumn international on Saturday (26 November) despite being forced to play with 14 men following the early sending off of Elliot Daly, England have now been left to digest the terrible news that influential performer Billy Vunipola is set to miss at least three months with a knee injury.
The powerful number eight had to be carted off the field before half-time and subsequently underwent surgery to repair cartilage damage. In addition to ruling him out of next weekend's crucial showdown with Australia at Twickenham in which England will attempt to match their record streak of 14 consecutive victories and achieve a whole calendar year unbeaten for the first time since 1992, such a lay-off means that Vunipola will likely miss much of the next Six Nations campaign which begins on 4 February 2017. He will also be a colossal loss for Saracens as Mark McCall's side attempt to replicate last year's Aviva Premiership and European Champions Cup double.
"Billy's been absolutely fantastic for England over the last 11 months and we wish him a quick recovery," head coach Eddie Jones said of the injury. "He's a very influential player in the set-up and there's no doubt he'll be missed for the game against Australia.
"But where there is an injury there's an opportunity for someone else. We've had five or six front line players missing throughout the series so I've no doubt we'll adapt and work that little bit harder this week. I'm sure the players will respond to this by going up a level and peak for this game."
England's formidable strength in depth has become a hallmark of their terrific success under Jones and has allowed them to maintain their winning run despite a pre-autumn injury crisis that caused much consternation with clubs and claimed Vunipola's fellow World Player of the Year nominee Maro Itoje, as well as the likes of George Kruis, now back in the fold after ankle surgery, James Haskell, Sam Jones, Mike Williams, Anthony Watson, Jack Nowell and Manu Tuilagi.
So who is likely to be given a chance to step up and prove their worth during Vunipola's absence? Ben Morgan would have been a major contender in many people's minds after impressing with a first-minute try in Gloucester's 24-20 defeat to Saracens on Sunday (27 November), although he was a glaring omission from the 33-man squad that has re-assembled at Pennyhill Park ahead of that meeting with Australia.
The logical choice, versatile back-row Hughes was born and raised in Fiji but qualifies to play for England via World Rugby's controversial three-year residency rule. The physical Wasps favourite, signed as a replacement for Vunipola in 2013, made his international debut as a second-half replacement for openside flanker Tom Wood during the 37-21 win over South Africa earlier this month and was perhaps fortunate to avoid being sin binned for a late body-charge on Johan Goosen. He also featured off the bench against his country of birth a week later but did little to enhance his claims for a regular starting berth.
Another of England's injury casualties, Clifford looked set to miss the entire autumn series after undergoing an ankle procedure in September. However, he has now been recalled by Jones after supplying a man of the match performance on his return for Harlequins against Bath with the caveat that he will continue to be assessed by medical staff throughout the week after requiring a Head Injury Assessment (HIA) during that 21-20 win at The Stoop.
Described as a "blooming good option at 8" by World Cup winner Will Greenwood, Beaumont has also been added to the squad who will prepare to face the Wallabies. Son of former England captain Bill, the Sale Sharks skipper, yet to win his first senior cap, travelled to Jones' pre-autumn training camp in Vilamoura, Portugal as cover for lock Courtney Lawes.
New Zealand-born Harrison deputised for Vunipola following his injury against Argentina, although was subject to criticism for his scrummaging and defensive nous. However, the four-cap Northampton Saints forward proved a frequent tackler and earned England a second-half penalty with some determined work at the breakdown.