Ringrose offers Ireland a point of difference
Centre's skills and decision making make Schmidt's side a more formidable force
The No 13 shirt was once the sole property of one man, but these days it is being passed around on an almost weekly basis.
At least it was until Garry Ringrose took to the pitch against Scotland and reminded everyone just how good a player he is.
It is a heavy mantle to bear, but the UCD man is the natural heir to Brian O'Driscoll and when he is at his best he almost eerily resembles the great Irish captain.
Last week, he made a difference to an Ireland team that had been a little blunt in their creative game - despite crossing for a host of tries - and vulnerable in defence.
Tomorrow, their game will receive a full stress test at Twickenham against an English team desperate to turn their losing run around and finish their campaign on a high.
Two years ago Ireland were at a low ebb when they pitched up at Twickenham and Johnny Sexton effectively tried to beat England on his own. It was a courageous display, but it fell well short.
Now the supporting cast is in place to allow the out-half to thrive.
Ringrose lightens his load on attack, offering a pacey game-breaker who possesses the capacity to make good decisions and pick the right pass when it's on.
And in defence, he is the key decision maker who knows when to shoot up and pressure or when to hold firm and use the touchline.
There are a myriad factors at play this weekend as two clever coaches put their tactical plans into action, but in the 23-year-old midfielder Ireland have a game-changer who gives them a point of difference as they look to build a Grand Slam-winning game-plan.
The Sexton decoy
Opposition defences have long known that stopping Johnny Sexton effectively stops Ireland.
So, the out-half inevitably draws a crowd when he gets the ball.
Against Scotland, however, Ireland used their play-maker as a decoy; drawing defenders to him like a magnet which allowed Ringrose to step in and up.
The first example came in the 26th minute when Sexton ran left off the back of a scrum, Conor Murray feinted to pass to him and then found Bundee Aki arcing the other way. He played the ball to Ringrose and the centre left Peter Horne for dead.
That didn't result in a score, but the ploy worked again on the stroke of half-time in the build-up to Jacob Stockdale's try when Sexton screamed for the ball and the Scots went with him, allowing Ringrose to play a neat one-two wraparound on Aki to put the winger away.
If the result is simply that England cannot pay as much attention to Sexton, then Ireland will be in clover.
More space for the out-half is a dangerous thing, but if the centre can stand in as an alternative first receiver then it supplements Schmidt's side's options and enhances their capacity to find and exploit space. It has added a layer of threat to Ireland's game.
Ringrose is a clever defender who manages his channel like a much more experienced player.
He endured a tough start to his season when he returned from shoulder surgery, but he appears to have gotten up to speed and against Scotland he showed good judgment when presented with difficult scenarios.
It wasn't perfect, but it was an excellent start considering his lack of game-time.
At one point during the second half, as the Scots briefly threatened to come back into the game, Ringrose pulled off a tackle that prevented a Stuart Hogg outside break, got back on his feet and tracked across to the far touchline where he nailed big second-row Grant Gilchrist.
His work-rate is excellent, but his perception and anticipation is also top drawer and will come in handy tomorrow.
Ireland know that England are struggling at the breakdown, they're fully aware of the issues Eddie Jones's first-arrivers are having and the numbers game they've been losing.
The Australian is convinced that the game is moving in the direction of fewer men in the ruck, but that hasn't been the way this tournament has gone and both Scotland and France dominated the tackle zone in their wins over the reigning champions.
Expect improvements, but Schmidt's side are one of the most proficient breakdown teams in the game and they are coming off a difficult exercise of their own against a good Scottish side.
Everyone is asked do their bit and numbers on backs are irrelevant.
If Ireland can secure quick ball for themselves and slow down Jones's side again, the hosts will become frustrated.
Keep the head
This Irish team is known for its good discipline, but the stakes are higher than ever and they need to keep their heads. Meanwhile, they have an opportunity to unsettle some of the home players who possess short fuses - with Kyle Sinckler an obvious target.
The Lion is a formidable athlete and a skilful operator, but he is prone to regular moments of madness. The red mist descends and he flips.
Alongside him is Dylan Hartley, back from injury and under pressure for his place, while Maro Itoje is capable of getting on a referee's bad side.
Owen Farrell is another who has had his moments, while Joe Marler and Dan Cole are on the bench and more than capable of moments of ill-discipline.
If Ireland can ruffle their feathers legally and through legitimate pressure, they may get reward.
Seize the day
From the moment they first gained possession in this tournament, Ireland have taken the game to their opponents and dictated the terms of engagement. Schmidt says they'd take 3-0, but that would go against their determination to dominate. They can't lose sight of what's got them here.
As Conor Murray said, it is not the time to retreat into their shells. Ireland must seize their opportunity just as they did against the All Blacks in Chicago.
If they do, the Slam beckons.
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