The unique rivalry between the two can be surmised by the remarkable stat that after 118 meetings between these old foes, they have 57 wins apiece.
Of course there will be Englishmen who claim that fixtures against the likes of Scotland and Australia are more significant but Anglo-Welsh clashes evoke a unique atmosphere. For Welshmen, beating the English is the one that really matters whilst the English seem to consider losing to the Welsh an insult to hundreds of years of dominance over the principality.
Wales have had the upper hand over the past few years after being routinely thrashed in each of the first five years of the naughties, but SaturdayÃ¢â‚¬â„¢s clash is unquestionably the most difficult to predict since the Welsh, thanks to a late Gavin Henson penalty, won 11-9 in Cardiff five years ago.
Neither side heads into the encounter with a great deal of confidence but England will have been buoyed by the late withdrawal of the Welsh loose-head prop Gethin Jenkins. Jenkins, who picked up a calf strain during training this week, is the second of the feted Lions front-row to drop out of the match after hooker Matthew Rees was declared unfit on Wednesday.
The scrum had been one area where Wales had anticipated posing their hosts some challenging questions and the negativity of the reaction to the injury in Wales has been so severe that the national coach Warren Gatland was irked into an impassioned lament at the pessimism which often prevails in the country.
His opposite number Martin Johnson will have been delighted at the news of JenkinsÃ¢â‚¬â„¢ injury, not only because of its potentially significant impact on the match itself but because it has attracted attention away from the public row between himself and former teammate Lawrence Dallaglio.
Dallaglio, a fellow World Cup winner in 2003, suggested earlier in the week that the current crop of players were struggling to emerge from JohnsonÃ¢â‚¬â„¢s shadow and the criticism extracted an angry response from the England manger.
The pre-game sparring has of course kept the hacks fill column inches throughout the week but with the match so delicately poised, few have offered much in the way of a definitive prediction. England, with home advantage and few disruptions to their starting XV this week should start as marginal favourites but such is the fragile mental state of both sides, early momentum could be crucial.
Both sides have named attacking sides encouraging the notion that we might be in for an open, attacking affair but with so much at stake, nerves may well get the better of the players.
The importance of making a winning start to the tournament has been emphasised, particularly for England with many pundits describing it as a must win match. Defeat however and the pressure on Martin Johnson will start to tell and it might not be long before whispers about his job security start to circulate.
Wales meanwhile are famously a team built on confidence. The core of the team who clinched a grand slam two years ago are still present and victory at the home of their greatest enemy would send the country into raptures. Five of WalesÃ¢â‚¬â„¢ past seven grand slams were kick started by a victory in west London and should they escape HQ with a win on Saturday then it would be foolish to bet against them doing so again.
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BIOGRAPHY: Hector Bellerin
BIOGRAPHY: Nemanja Matic