A mouth -watering contest awaits at Twickenham on Saturday when Ireland take on the Championship holders with the intention of showing that their victory in Dublin last autumn was no flash in the pan.

The row over Martin Johnson's moment of indiscretion in his last Zurich Premiership appearance will be put the side for at least 80 minutes while these two sides do battle in what is being heralded as the Championship decider.

Johnson himself will be relishing the opportunity to take on an Irish side keen to grapple for superiority in the northern hemisphere. He has missed the last two clashes with the men in green , most notably having to watch from the Lansdowne Road stands last October as another Grand Slam slipped from his side's grasp.

England enter the contest with the scalp of Scotland but Ireland's hammering of Wales and the resignation of their coach Graham Henry stole the headlines and added even more spice to what was always going to be th emost eagerly anticipated clash of the tournament.

Fortress Twickenham is sure to play its part. Clive Woodward's men have won thirteen in a row at the home of rugby, and Ireland coach Eddie O'Sullivan has urged his players not to be daunted.

"There is a psychological aspect to playing at Twickenham. The players have to be mindful of the consequences of not playing well there. They are very focused, but there are no misconceptions of the size of the task in front of them. England were not up to par against Scotland, but they still ran in four tries."

But skipper Johnson, responding to suggestions that home advantage is worth a start of several points to England, insisted: "It's only because we have played well at Twickenham that we have won games.

"Every team plays better at home but if we go out and miss tackles and turn the ball over we will be behind, whether we are at Twickenham or not. It's only an advantage being at home if you play well."

Although Saturday's team will contain only five members of the side deprived of last season's Grand Slam by Ireland's 20-14 victory in October (Jason Robinson, Jonny Wilkinson, Greenwood, Richard Hill and Neil Back), Johnson still believes it is important to consider what happened at Lansdowne Road.

"It's quite amazing that in only four months there have been so many changes, but there is still a lot of relevance to that game. We have to learn from it and try and counter the things they do well," he said.

Just as the contribution from his club side at Leicester is a big influence in the England pack, Johnson knows just how important the Munster effect is for the Irish. "I watched Munster play at Stade Francais and it was one of the best wins in European Cup history," he said.

Lions Eric Miller and Malcolm O'Kelly are the only changes from the Ireland team that beat Wales and the continued absence of skipper Keith Wood, so instrumnetal in England's downfall last October, may prove decisive.

Miller has recovered from the stomach bug which kept him out of the Wales game and he replaces Llanelli's Simon Easterby in the back row. O'Kelly comes into the second row as a replacement for Munster's Paul O'Connell, whose try-scoring international debut against Wales was cut short by concussion.

Martin Johnson leads an England side showing one change from the team that defeated Scotland 29-3 at Murrayfield nine days ago. Gloucester prop Phil Vickery returns to the starting line-up - despite not having playing since January 12 - instead of Bristol tighthead Julian White. Woodward has made two switches among the replacements, recalling fit-again Leicester forwards Dorian West and Lewis Moody.

A victory by more than 18 points will see England become the first northern hemisphere side to top the world rankings but that is unlikely with even the England skipper admitting, "it could be three points, it could even be a one point game."

Ireland, the last Celtic nation to win at Twickenham, stunning Will Carling's side 13-12 in 1994, are capable of producing another shock but once again it is England you feel who hold the key to their own destiny.