Six Nations: Pleasant problem for England - 10 into three won't go

The emergence of new back-row talent leaves Lancaster with an embarrassment of riches that could mean some big names being left out in the cold

Most unusually, Stuart Lancaster made a mistake this week. Going through his back-row options for the testing months and big matches ahead, he identified nine contenders when he meant to name 10. Will Fraser, the uncapped Saracens flanker, was the man who failed to receive a mention – an omission that left the head coach embarrassed, if not mortified.

"I forgot Fraser? Ah, that was an error," Lancaster admitted. "He's definitely on our list. When we brought him in for training last month, he did a lot of good things and made a really positive impression. I like his character. He's made of the right stuff."

Fraser can rest easy in his bed, then: he'll get his chance, probably in Argentina in June, and if he makes the most of it, we can expect to see him in the new elite player group when it is pieced together later in the summer. But for every loose forward who enjoys a good night's sleep these days, another lies awake in the small hours fretting over his international future.

Everyone wants to be a part of the England project in the build-up to the home World Cup in two and a half years' time but, with tournament squads limited to 30, only half a dozen specialist back-rowers will make the cut. Maybe only five.

The sudden emergence of two more yet-to-be-decorated newcomers, the Worcester flanker Matt Kvesic and the Wasps No 8 Billy Vunipola, has muddied the waters. Both are pressing their cases in training and both are likely to kick on strongly by moving to stronger, more successful clubs next season: Gloucester in Kvesic's case, Saracens in Vunipola's. Throw in the heart-warming return of Tom Croft, following his successful recovery from a neck injury so serious that it could have wrecked his life as well as his career, and it is possible to forgive Lancaster his lapse of memory.

While other areas of the Test team have settled down – for instance, the coach's ideas on how the midfield and half-back combinations might work have crystallised in recent weeks – the back-row equation is growing more complex by the week.

Not even Chris Robshaw, the captain, is completely secure, despite his Trojan-like work rate and honest-to-goodness leadership skills. "Robshaw has done brilliantly: he's playing as well as he can possibly play and he's a popular captain for all the right reasons," said one former England forward and skipper this week. "Lancaster was correct in asking him to lead the team, just as he was correct in getting rid of some of the 'big characters' who ended up undermining things at the last World Cup.

"But I think the culture in the camp is now strong enough for him to pick his very best players, even if they are a little on the difficult side. In my opinion, Robshaw is not a natural open-side flanker, effective though he has been in recent matches. To my mind, the best No 7 in Europe right now is Steffon Armitage, and if England want to be as strong as they can be, they should be thinking very carefully about bringing him in."

Armitage is currently playing top-flight club rugby in France with Toulon, and Lancaster has shown no inclination to cast his net that wide – partly because his employers at the Rugby Football Union have turned their face against selecting from overseas, and partly because he is not much interested in individuals who rock the boat. In the cold, dim light of the confessional, Armitage himself would acknowledge that he is not the easiest player to manage.

As things stand, there is little prospect of Lancaster picking from the Riviera; or, indeed, from anywhere else on mainland Europe. He feels, with some justification, that he has quite enough back-row candidates to be going on with, including some genuine No 7s.

The congestion is already of the "M25 on a Friday night" variety and as the coach goes in search of the right mix – of what the former England No 8 Dave Egerton once called "the ideal balance of footballers and bastards" – some very ambitious players could soon find themselves surplus to requirements.

Lancaster's back-row contenders

Open-side flankers

Will Fraser Saracens

One of the men who could really upset the applecart over the coming months, the 23-year-old rookie was a big hit with the coaching team after being called into camp for the once-over last month. A natural breakaway of the hunter-gatherer kind, as opposed to the manufactured sort.

World Cup chances 3.5/5

Tom Johnson Exeter

Recast by England as a No 7 after playing virtually all his big-time rugby as a No 6, he is likely to be squeezed in the numbers game and slowly cast aside. If this is scant reward for his courage in adversity against the Springboks last summer, it is also reality.

World Cup chances 1/5

Matt Kvesic Worcester

Another uncapped contender, he can expect to tour Argentina this summer. The head coach has been talking about him for ages and you can see why: strong on the carry and hard on the ball, he has touches of the low-slung Wallaby maestro David Pocock about him.

World Cup chances 3.5/5

Chris Robshaw Harlequins

The statistics say the captain is playing a blinder, but no one with an eye for rugby needs figures to confirm the bleeding obvious. As long as he holds his form, he holds his place. His problem? The safety-net move to No 6 is increasingly unlikely to be available.

World Cup chances 5/5

Blind-side flankers

Tom Croft Leicester

The 2009 Lion was once regarded as a "luxury pick": coach-speak for a player who does certain things brilliantly while not doing others at all. The word now is that his ugly game is nearing the same level as his beautiful one. If true, he will make a cast-iron case for selection.

World Cup chances 4.5/5

James Haskell Wasps

Almost as versatile as he is confident – he has played Test rugby in all three back-row positions – the globe-trotter from Windsor has done well to force his way into the head coach's affections. Yet for all his will and energy, he could easily find himself stuck in the logjam.

World Cup chances 2.5/5

Tom Wood Northampton

Authoritative, utterly ruthless and as tough as old boots, the 6ft 5in Saint seems certain to play a significant role over the next two years. Can the coaches find a way of pairing him with the equally tall Croft? The idea sounds attractive for they would balance each other perfectly, but it will take some finessing.

World Cup chances 5/5

No 8s

Ben Morgan Gloucester

Still a work in progress, but if the big man can finally find a way of stringing three games together without twisting, spraining or otherwise mangling something, he could yet nail down the position. There is, however, competition coming his way from someone equally big and injury-prone.

World Cup chances 4/5

Billy Vunipola Wasps

Uncapped, but close to being unleashed. Only just out of his teens, the Australian-born Tongan who has declared for England has South Seas dynamism running through his veins and could, if used intelligently, bring a new dimension to the red-rose attacking game: 20st-plus, highly skilled and mobile? Crikey.

World Cup chances 4/5

Thomas Waldrom Leicester

The light is beginning to fade for Thomas the Tank as he disappears into the long tunnel of declining hopes. The naturalised New Zealander played his heart out in Port Elizabeth last June, but a poor game against Australia before Christmas cost him dear. Back of the queue, suddenly.

World Cup chances 1/5