2019 Rugby World Cup: Patrick McKendry - Japan upset over Ireland proves All Blacks have the right gameplan

Japan's shock World Cup win over Ireland in Shizuoka is not only good for the host nation and the tournament itself, it is more evidence that the All Blacks' plan to play an up-tempo game based on width and speed of thought and feet here is the right one.

It is more evidence to suggest, too, that the hours spent sweating under the hot sun on their training pitch in Beppu as the All Blacks prepare for Wednesday's match against Canada in nearby Oita, and the one four days later in Tokyo against Namibia, will be time well spent.

Ireland were simply overwhelmed in the second half of their 19-12 defeat to the Brave Blossoms. They were beaten by a combination of an inspired Japanese side who had been preparing for this match for 12 months, plus probably the heat, a lack of conditioning and the failure to find another gear on attack when they needed one.

Their set piece became frayed at the edges – they gave away a scrum penalty when on attack near the end of the first half and in the second half they lost an attacking lineout just when it seemed they were getting back on top. They wouldn't get another opportunity.

The tournament has just been turned upside down but so has the Irish team's world and they will be desperate to win well against Russia and Samoa and hope that other results go their way so they get back to the top of their pool and avoid a quarter-final against New Zealand who have the ability to hurt them far more consistently than Japan did.

What was strange was that the Irish appeared to have the Japanese worked out. The hosts were vulnerable under the high ball in their opening win over Russia and they were in the first half in Shizuoka when giving up two tries after being outjumped in the first quarter.

But rather than build on their advantage the Irish withered in the face of the Japanese comeback. Initially it was a slow burner but the flames grew by the minute and once the crowd sensed an upset the house was fully ablaze.

Once replacement back Kenki Fukuoka scored to put his side ahead in the 58th minute the Irish were in big trouble because their physical presence had all but disappeared and normally dominant forwards such as Peter O'Mahony and Rory Best looked like old men who couldn't handle the pace.

Is this result an aberration or a sign of things to come? All Blacks coach Steve Hansen has said a few times recently that, currently, defence is king in rugby but that attack will slowly but surely find a way to overcome before the cycle repeats itself.

Ireland's defence was virtually impregnable against Scotland, and they remain dangerous sudden-death opponents – especially in wet conditions. But clearly they are vulnerable to teams playing with energy, enthusiasm and ambition and so far in this tournament the All Blacks top that list of qualifications along with Japan, South Africa and possibly France.

The All Blacks were in a bit of bother against the Boks in Yokohama in the first quarter but turned the match on its head with two pieces of magic in five minutes. They could have had another try in the second half when Beauden Barrett broke from his own line.

The Irish don't appear to have that ability to conjure something from nothing when under pressure, and with key playmaker Johnny Sexton carrying a thigh injury, it's suddenly not so rosy for the men in green.

Japanese eyes are smiling though, and the supporters of fellow pool nations Scotland and Manu Samoa probably just got a lot more interested and in fact that should go for the rugby world in general. Attack is king; long live attack.

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