Twickenham makes its bow in this year’s championship by hosting this pivotal clash between two sides that are looking in good nick.
Ireland can claim the Triple Crown and take a giant step toward the Grand Slam if they can win at Twickenham for the first time since 2011, whereas England cannot lose if they are to keep their title hopes alive.
Ireland’s wealth of experience will provide a stern test for England’s young side. Can they deliver in front of an expectant home crowd, or will Ireland’s old heads win the day? It’s going to be fascinating.
The injury to England tight head Dan Cole has exposed a rare lack of depth on that side of the Red Rose scrum.
Bath’s David Wilson will fill the shirt on Saturday, but he has played just 60 minutes of rugby in two months.
All the noises that are coming from the England camp say they just hope he can last 60 minutes before they are forced to expose the callow Henry Thomas to the power of Cian Healy.
Healy was in great form against Wales both in the scrum and with his ball carrying.
He epitomises the modern-day prop forward, whereas Wilson seems more of a throwback—he's a capable scrummager and lifter but limited with the flashy stuff. He has never had more pressure on his sizable shoulders than he does coming into this contest.
If Healy gets the better of him, it will be a tough afternoon for the English front row and could allow Ireland to build up a lead through scrum penalties.
Former England centre Jeremy Guscott told BBC Sport that England will win if Wilson doesn’t run out of steam. That is a big if.
Both Paul O’Connell and Courtney Lawes have been in great form this season.
Lawes has risen to the challenge of calling England’s lineouts in addition to his role as ball-carrier and big hitter.
O’Connell has banished his injury woes to regain his very best form. Both men run lineouts that give the opposition very little, so it will be a key facet of the game should one lineout start to seriously unsettle the other.
Lawes will also have to play a large part in stopping the Irish rolling maul, which has proved so successful thus far in the championship.
O’Mahony was man of the match in Ireland’s demolition of Wales.
He beat the vaunted Welsh back row all ends up at the breakdown, stealing the ball on the floor and winning a number of penalties for his side.
Tom Wood and his back-row colleagues in the England camp will have been carefully dissecting the video of O’Mahony’s performance in that game to devise a plan to stop the Munster skipper from doing a similar job on them.
Playing the "jackal" isn’t necessarily Wood’s natural role, but he will have to get down and dirty if O’Mahony finds the form he showed against the reigning champions.
The only two fly-halves picked for last year’s Lions tour come face to face at Twickenham.
Sexton is the better running fly-half of the two, but Farrell has shown so far this campaign that he is keen to take the ball flat and break the line more than he has so far in his international career.
While both defences might make line breaks for either man hard to come by, the kicking duel between these two could swing the match in someone's favour.
Sexton delivered a master class in territorial kicking against Wales. If his range finder is on song again, it will be up to Farrell to match him.
Both full-backs have been playing well thus far, and their decision making will be key on Saturday.
Kearney knows he has the ability to put Brown’s inexperienced back-three partners Jack Nowell and Jonny May under pressure with his aerial bombs, while Brown’s capacity to join the line and counter attack well will force Kearney to measure his kicking with pinpoint precision.
Both men have found the try line in the championship and will be keen to do so again at Twickenham.