England number eight crisis: 'This is where Eddie Jones earns his money'
England are reluctantly getting used to life without Billy Vunipola.
The Saracens number eight has started only three Tests since 2016 and won't add to that tally this year after being ruled out of the autumn internationals with a broken arm.
However, with South Africa, New Zealand, Japan and Australia visiting Twickenham on consecutive weekends, coach Eddie Jones has a new problem.
Wasps' Nathan Hughes is facing suspension and Exeter's Sam Simmonds is sidelined with a knee injury, meaning Jones' two usual deputies at the back of the pack are out of action.
Who might step into the breach to face the best of the southern hemisphere?
England and Harlequins scrum-half Danny Care and former club and country colleague Ugo Monye talked through the options on Rugby Union Weekly. And found no easy answers.
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A change of style as well as personnel?
Ugo: The back row used to be such an area of strength and options for Eddie Jones. Now it is starting to look pretty bare.
He will be having nightmares. England have got a massive playing pool to choose from, but when you are losing front-line warriors ahead of such a testing series that puts his squad under strain.
It is made trickier by the style Jones has worked on since he came in at the start of 2016.
He wants a big ball-carrying number eight. Exeter director Rob Baxter joked recently that Simmonds is 30kgs short of Jones' ideal and he certainly has not had the number of caps and game time that Baxter, Exeter fans and I would have liked to see.
If you don't have a heavy-duty, imposing ball-carrier in Vunipola's mould that changes the whole dynamic of the back row.
You could run with a more mobile, lighter-weight number eight and make up for it in other areas, perhaps with specialist second row Maro Itoje at six and more of a destructive ball carrier at seven.
Jones is paid a lot to make these decisions as England coach, this is where he earns his money.
Who could come in?
Gloucester's 29-year-old Ben Morgan, who won the last of his 31 caps in 2015, told BBC Sport earlier this week that he still hoped for a recall and was watched by Jones in his team's win over Castres at the weekend. He is one of many who comes into contention.
Danny: Ben Morgan is a brilliant player, every time he plays for England he plays well. He has had countless man of the match awards from when I've played with him.
He is a big old boy, imposing his physicality on the match, but he also understands the game well.
There are two pretty decent eights at Harlequins with me in James Chisholm and Jack Clifford - it would be brilliant to see either of those get a sniff.
Ugo: It depends what you want in your squad.
If you are looking at the next cab of the rank, the next long-term solution, then that might be Bath's Zach Mercer. He captain England's Under-20s to the final of their World Championship in 2017 and has put on a bit of bulk over the summer.
Clifford also comes into that category, but he has not played a huge amount of rugby [recently because of injury].
The other option is someone who is tried, tested and experienced.
For me Ben Morgan is probably the only big ball-carrying number eight left in this country and has played well this season.
Exeter's Dave Ewers has been operating massively in the last few weeks, while Brad Shields, who belatedly made his Wasps debut at the weekend after fracturing his cheekbone, is a versatile back row option.
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