Here, now, comes the Rising Sun chaos. Peter O'Mahony has the ball and with not much support around him, he launches the novel sight of a chip kick for Keith Earls to hare onto.
It's a decent kick but not what we imagined seeing. Earls is quick but Japan recover and Kotaro Matsushima takes possession and looks up to effect a relieving kick from behind his own goal line. Except he sees a few yards of space between Earls and the touchline.
A shimmy and Matusushima is gone, free and heedless as the wind. Japan, or at least its citizens here in the bowl of Shizuoka, explode in delight. Anything could happen now. Which is precisely what Joe Schmidt and Ireland did not want. It's turning dusky and it's still warm. For atmosphere, this place could rival Ellis Park or old Lansdowne. There are intimations of Brighton - the miracle of four years ago, with the audacity, the sense of an on-the-edge-rugby country with a strange and unique affinity for the sport, suddenly electrified by their talent for hardwiring into a brand of rugby that is impossible to recreate on the training ground. It's what the world had come to see: Japanese rugby bursting on to the world stage again.
Ireland are 16-12 down with 20 left to play: it’s far from lost on the scoreboard but crucially, they are playing in an unstructured and random world of rugby now. The playbook has been ripped up. It’s rugby with a sevens mentality. And referee Angus Gardner seems quick to punish the Irish in contact after contact, for not rolling away, for not releasing. He seems persuaded by what is happening here. And big names are falling like flies.
Rory Best has left the theatre. Rob Kearney has gone off injured, forcing Jacob Stockdale to switch to fullback and a just-on-the-field Luke McGrath out to the left wing. This is a thousand miles away from anything that would have been spoken in the calm, hot midweek days of Shizuoka. Japan had found its rugby voice.
What we had imagined - a mass green invasion, an Irish charm bombardment, a few lusty rounds of The Fields of Athenry as Ireland put the hosts away in the final quarter - suddenly seemed fanciful. This was Japan experienced for the first time as somewhere foreign and hostile and indifferent to the need of her visitors.
It was misery in the heat for Ireland but a dream occasion for the Rugby World Cup. Japan's mid-afternoon national television audience discovered that they had a rugby team capable of living with one of the superpowers from the cold and wetter edges of western Europe. From the neon streets of Tokyo to the old fishing villages of the northern coast, word must have spread that Japan was rising, all right.
The jitters they endured on the opening Friday night disappeared from the moment that Lomano Lemeki and Ryohei Yamanaka secured two high early questioning kicks from Jack Carty and found touch with safe, meaty returns. From then on, Japan engaged in a way that must have thrilled their coach Jamie Joseph: ferocious in the tackle, brilliantly free in their running game, sufficiently stir-crazy to run a three-man lineout just a few metres from their own try line and, most importantly, playing as though they belonged in the arena.
Japan’s reputation for slick ball movement and freestyle running precedes them. But the big thrill for the local crowd here lay in the heavyweight confrontations. Just after Yu Tamura’s 18th-minute penalty, Lemeki led a heave in which the Irish conceded 15m of ground. Japan turned the ball over for not releasing. But it didn’t matter. The locals had seen the European team in sharp retreat.
Ten minutes later, the busy Lemeki tried was swallowed up by the three green shirts. For several seconds, the only visible part of him was his feet and legs swinging wildly and at least a foot off a ground, like a toddler hauled away from the playground by an out of patience parent. But then, somehow, he was clear through and the promise of a Japan try filled the afternoon.
When Japan turned over an Irish scrum on the half-hour mark, loosehead prop Keita Inagaki beat his chest and let a howl into the afternoon. Through all these moments, you could see the belief flooding through the team, through the local crowd and maybe as far as the western islands. Number eight Amanaki Mafi squeezed an hour's worth of tackles into the 29 minutes before he had to retire with tenderised ribs. A huge roar filled the sky for his replacement Michael Leitch, the enduring symbol of leaner times for Japanese rugby. And they remained true to their two golden rules. If we can run the ball, we run the ball. If we can't run the ball, we run it anyway.
If they were behind on the scoreboard, it was down to the usual unforgiving solidity of Ireland's defensive line and the scoring efficiency which is becoming their calling card. Twice, Japan were caught out by sensational kicking range of Carty, who delivered a crossfield kick for Garry Ringrose to catch and touch down and later a delicate chip on Japan's try line which he tipped back for Rob Kearney to crash home from close range.
Ireland weren't imposing their brand of rugby and weren't controlling the game as they have done on so many Six Nations afternoons. Still, James Ryan and Josh van der Flier were at the forefront of Ireland's ball-carrying game. The gong went for half-time and it was Japan camped on Ireland's 22, still searching for the score that would have set this pretty stadium on the hill ablaze. It was, surely, just a matter of time before the natural order asserted itself.
Early in the second half, it became apparent that the dramatic shift in mood and possession that had occurred late in the first half was not an illusion. The assumption was that Japan might target the vulnerable Scots. Instead, they smelled a chance here. It was no real surprise when Kenki Fukuoka finally dashed over in the corner on the hour mark for Japan’s first try. Tamura nailed the conversion and a later penalty for a 19-12 lead.
By now, Bill Beaumont and the other executives of world rugby could have been forgiven for padding around in full kimono and keta. This was the 40 minutes that the tournament needed; the hosts taking their game to a team that came in here as the dark fancy to do something special.
The evening tripped into the hallucinatory when Fukuoka picked off a Jordan Larmour pass and rushed for glory. Earls and Larmour hunted him down but it left Japan with a scrum in front of their posts and the seconds ticking down.
In front of the dugout, the Japanese replacements stood, arms locked. Nearby, the Irish sat slumped and devastated. It was a tough result for an Ireland outing that included dauntless performances from Ringrose and Farrell through increasingly impossible minutes.
At the gong, the red and white jerseys celebrated like they had just won the World Cup. In a way, they had. The vanquished Irish were hugely respectful afterwards before leaving the field to get their heads straight. Japan’s Blossoms lined up to take a famous, famous bow to their countrymen.
