IT is 17 months until the start of the 2015 Rugby World Cup, but from an English perspective, the countdown begins tomorrow.

After a satisfactory start to the Six Nations, with a narrow defeat in Paris preceding a facile success in Edinburgh, the next two matches will tell us much about the realistic ambitions of Stuart Lancaster’s side. Are they genuine World Cup contenders or destined to be hosts thrown out of their own party?

Ireland visit Twickenham tomorrow, with Wales turning up at HQ a fortnight later, and while the fate of the Six Nations Championship could well be decided by those two games, it is just as important that England lay down a powerful pre-World Cup marker.

The ‘Twickenham factor’ will have a huge impact on England’s World Cup chances next year, with three of their four pool matches scheduled for their home stadium, including the key Pool A clashes against Australia and Wales, and all of their potential knockout games guaranteed to take place at their London home.

Make Twickenham a fortress, and Lancaster will have done much to emulate Sir Clive Woodward, who built on a formidable home record to achieve World Cup success.

The signs are reasonably positive at the moment, although admittedly nothing like on the scale of 2003 when England recorded 22 consecutive home victories before heading off to Australia to claim the Webb Ellis Trophy.

The Lancaster era has witnessed home defeats to Australia, South Africa, New Zealand and Wales, although victories over the first two of the Southern Hemisphere sides have to be factored into the equation.

Recent home performances have been positive, most notably last autumn’s win over Australia and thrilling defeat to New Zealand, when England pushed the all-conquering All Blacks incredibly close and briefly headed them in the second half.

Ireland did the same in Dublin of course, and while France could yet head into the summer as Six Nations champions, it is tomorrow’s game against the Irish and the following game against the Welsh that represent the challenges England really have to overcome if they are to cement their claim to be the strongest World Cup challengers in the Northern Hemisphere.

It is 2002 since they beat both Celtic nations at home in the same Six Nations, and in the past ten tournaments, Ireland and Wales have been responsible for five of England’s six home defeats. Beat both sides this month, a key pre-World Cup box will have been ticked.

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GETTING BETTER: Owen Farrell

Are England in a position where they can do that? Time will tell. There has been a huge churn of players in the last few seasons – just three of the players who started the home game with Ireland two years ago will start tomorrow, with another, Mike Brown, stepping up from the bench – but you get the feeling Lancaster is gradually beginning to settle on the side he envisages kicking off the World Cup campaign.

Some of his key units are coming together, although perhaps the most important, the front row, will be disrupted tomorrow by an injury to Dan Cole.

Former Newcastle Falcons tight-head David Wilson will replace Cole, and the impact of England’s scrummaging could have a major impact on the final outcome. Ireland’s pack has been reborn in their opening two matches, with their rolling maul all but obliterating Wales two weekends ago.

England have been working on a way of stemming the green tide, but even Lancaster would have to concede that it would have been easier with Cole in the side.

That said, however, the rest of England’s forward pack remains intact, featuring names that can already be inked into the World Cup line up.

Courtney Lawes and Joe Launchbury have formed a formidable second-row pairing in recent games, and it will be interesting to see how they meet the challenge posed by a re-born Paul O’Connell.

Skipper Chris Robshaw has silenced the debate about his suitability to play at open-side flanker, while at number eight, Billy Vunipola has been England’s biggest find for quite some time. Irrepressible at the breakdown, expect Vunipola to be instructed to disrupt Jonathan Sexton at every opportunity tomorrow.

As ever with England, questions still remain behind the scrum, although in Danny Care and Owen Farrell, Lancaster has at least constructed a half-back pairing that complements each other perfectly.

Farrell’s game management has improved no end in the last 12 months, to the point where he can rightly go into tomorrow’s game considered Sexton’s equal. Care’s form remains more erratic, and he will need to erase the memories of last season’s struggles against Conor Murray, but his ability to inject pace and unpredictability into England’s play is a priceless commodity at the highest level.

The centre pairing is still a work in progress, with neither Luther Burrell nor Billy Twelvetrees guaranteed a World Cup place despite the former’s strong showing in the opening two Six Nations games and the latter’s undoubted improvement since a difficult autumn.

Manu Tuilagi will have to be factored in somewhere once he returns from injury – possibly before the end of the Six Nations – and the blend between creativity and power still doesn’t feel quite right. Perhaps, in the modern game, it never will.

Brown is a world-class full-back, and while Jack Nowell and Jonny May remain relative novices on the wing, they are both making a decent fist of staking a claim for an extended run in the side in the absence of injured duo Marland Yarde and Christian Wade. If nothing else, Chris Ashton’s ship certainly appears to have sailed.

Plans are coming together, but events have a strange way of rewriting them, and the outlook would look considerably different if England were to fall flat on their faces in the next two games.

If, however, they record back-to-back victories, the rest of the World Cup countdown would feel that much easier to negotiate. As things stand, there are 18 games to go. By the time the tally gets to 16, the future should be easier to assess.

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The bad run continued as Merry King failed to finish in Haydock’s gruelling Grand National trial last weekend. The charity pot is currently down to a fiver, so there’s going to have to be some serious thinking ahead of this weekend’s racing. Follow @scottwilsonecho on Twitter or log on to The Northern Echo website on Saturday to follow tomorrow’s tip.