Ireland began with bone-cracking intensity and soon mixed it with a skillset we haven't seen before from the men in green. Paul O'Connell, the giant veteran lock, was using the ball like an outside back, not something he has always been accused of.
Who else? Prop Cian Healy, the haka hater, running over the top of Richie McCaw. Flanker Sean O'Brien signalling his intent by shoving little Aaron Smith out of the way in the opening minutes. Adding to this wave of muscular physicality and intelligence was the crowd, 50,000 people urging, cajoling, cheering. They really did feel like a 16th man.
Reasons why the All Blacks fell into that green-tinged pit? What if Cruden, who had earlier so magnificently used his left boot to set up Julian Savea's try, had found touch late in the first half with the All Blacks only penalty at that stage? With less than five minutes of the half to go, Ireland would have been under extreme pressure. The kick, alas, was short, the chance lost. As it turned out, Ireland finished the half on the front foot, familiar territory in this match.
Another virus had gone through the camp, just like last year in the final week against England which finished in defeat. Luke Romano spent a night or two in isolation, along with some of the management. How much difference did that make? Not much, probably. His replacement Brodie Retallick is world class, after all, but Steve Hansen's men seemed flat.
The referee Nigel Owens? One penalty in the first half awarded to the All Blacks suggests Ireland were being extremely disciplined. Owens began the second by penalising McCaw for not releasing the ball in a tackle - a marginal call given his reluctance to penalise Ireland for similar transgressions. Jamie Heaslip was allowed to tackle replacement hooker Dane Coles, not release him, and then steal the ball despite being off his feet. There was a feeling of 'anything goes' in this area.
These questions will go on and one throughout this week and beyond as this victory is discussed but one point above all others was obvious. Ireland just seemed more up for it. The All Blacks forwards looked a bit timid in comparison. As a result the backs too often looked flat-footed, and although Ma'a Nonu had his moments, there seemed to be a disconnection between him and Ben Smith.
Time for the positives, and the All Blacks deserve credit too.
Ben Franks' try was a testament to an increased fluency and a determination by the forwards to smash their way over the advantage line. Kieran Read's sleight of hand wasn't bad either.
Beauden Barrett was outstanding when he came on at fullback, replacing wing Cory Jane. The capacity of McCaw and Read to take on yet more work to get their side across the line. The try by Ryan Crotty and the conversion, on the second attempt by Cruden.
A remarkable finish, almost five minutes after time was up. It was so cruel on Ireland, a most unlikely of victories for the All Blacks. A perfect season but not a perfect performance.
"It wasn't in the script, that's for sure,'' Hansen said afterwards.