There was a brief moment – very brief, it must be said – when it felt as if Ireland's Grand Slam hopes might just be in the balance here. With Joe Schmidt's team down to 14 men midway through the first half, and England having scored through Elliot Daly to ignite hopes of a comeback, Johnny Sexton went off for an HIA, blood pouring from his face.
Ireland's talisman, the man who had dropped that miraculous goal in the final minute in Paris last month, without which this historic achievement would have been Dead On Arrival, was out of the game. How would Ireland cope?
Rather well, actually. Youngster Joey Carbery came on, Ireland saw out the rest of Peter O'Mahony's time in the bin without conceding again, and Jacob Stockdale scored with the final play of the half thanks to England's decision to repaint the dead ball line a few yards on from the old one.
If 'blue paint-gate' summed up England's shambolic campaign then Ireland's success without Sexton summed up theirs. They are far more than a one-man band.
The Leinster man is still irreplaceable, of course. And Sexton's contribution to the game was not insignificant. It was Sexton who launched the perfectly judged up-and-under after just five minutes that will give Anthony Watson nightmares for months to come.
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But this was not his day. It was Ireland's. The whole team. Sexton came back on to the pitch for the start of the second half, but was clearly not 100 per cent, leaving goal-kicking duties to Conor Murray and cutting a peripheral figure before being substituted definitively for Carbery after 67 minutes.
In his absence, the team stood up brilliantly. From Tadhg Furlong at tighthead – arguably the best in the world in his position now and man of the match here – through to Murray, whose control was absolutely exemplary, to Rob Kearney at full-back, Ireland were everything England were not. They were clinical, disciplined, cohesive.
Some individual moments stand out; Keith Earls recovering to make a brilliant tap-tackle on Daly; 21-year-old James Ryan, his jersey and shorts covered in blood (someone else's), finishing on the winning side yet again, adding to his burgeoning reputation; Ryan's former Under-20 team-mate Stockdale, Ireland's new try machine, notching his seventh of this campaign, and his ninth in 11 tests, to become the most prolific one-campaign try-scorer in Six Nations history. Neither Ryan nor Stockdale has yet tasted defeat in an Ireland jersey.
This was a day to celebrate Ireland's team work, though, rather than laud any one individual.
Sexton remains their star, Schmidt's on-field lieutenant. And having just missed out on Ireland's last Grand Slam back in 2009 (he made his Test debut later that year) it was fitting that the finest No 10 in the northern hemisphere added that gong, and a Triple Crown, to his cabinet, to sit alongside his Six Nations and the Heineken Cup medals. His partnership with Murray at halfback remains crucial to their World Cup quest.
But it was the sight of Ireland en masse, embodied by Rory Best – their captain but so often one of their unsung heroes – lapping the Twickenham pitch with their children afterwards, about to give London a St Patrick's Day shoeing as they did England, that will linger longest in the memory.
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