Since the advent of professionalism and the rise in the status of the Rugby World Cup after its rushed introduction in 1987 against the wishes of the four unions in Britain and Ireland, the sport at international level now tends to operate in four-year cycles.
The completion of every tournament is greeted with a raft of international retirements with our own Rory Best and Italian captain Sergio Parisse amongst a swathe of high profile, multi capped leaders ready to depart the stage after the completion of their involvement here in Japan.
Every decision the coach makes in that cycle is undertaken with the implications of the tournament in mind, even more so from two years out.
Yet, of all competitions, a World Cup tends to take on a life of its own, when even the best-laid plans get thrown out the window.
It is so different to the standard tours that international squads take on these days and in a country like Japan with its vast cultural differences and playing conditions, the players have to adapt quickly or be left behind. The only experience that comes anywhere close to matching it is a Lions tour but the difference there is the depth in quality with your squad selected from the best of the four home nations.
Much has been made of the manner with which so many of the Irish players found it so difficult to operate at full tilt in just their second game of the tournament against Japan, six days after their opening encounter. Apparently, in very high humidity there is less oxygen in the air and that plays a part in explaining the Irish defeat.
Japan knew what needed to happen to take this Irish side out of its comfort zone and succeeded in achieving that. Who would have thought that a quality Irish front five, that completely demolished the Scots, would find it so difficult to subdue their Japanese opponents?
Wales started their campaign with a clinical performance against Georgia, a bonus point in the bag by half time when they led 28-0, yet only drew the second half 14-14. That collapse after the break was in evidence again in that brilliant contest against Australia on Sunday, a game that rivaled New Zealand’s win over South Africa as the best in the pool stages
A superbly struck drop goal from Rhys Patchell four minutes into the second half gave Warren Gatland’s men a buffer of 18 points. They needed every one of them as they were hanging on for dear life in the demanding conditions when the Wallabies threw everything at them.
Having scored ten points in a blistering two-minute spell in the opening half, they only managed three more after that Patchell strike. He did superbly well from the boot and his clutch penalty kick with Wales hanging on for dear life on 71 minutes offered some badly needed breathing space.
Wales did brilliantly to win this one, especially when they lost Dan Bigger on the half hour mark when he paid a high price for a thunderous tackle on Wallaby powerhouse centre Samu Kerevi.
Patchell wouldn’t even be here if Gareth Anscombe hadn’t got injured in the warm-up against England, yet rose to the occasion in the key game in their pool. He wasn’t in Gatland’s thoughts a few months ago.
Likewise Wallaby coach Michael Cheika, who has had a torrid time in the job since leading Australia to the final four years ago, has always asked to be judged on this World Cup.
Like Joe Schmidt, he has been planning for this for years yet despite that, incredibly, fielded a starting backline against Wales that had never played together as a combination before.
That is exactly what I mean by a World Cup tournament assuming a life of its own. It asks questions that no other competition does. Circumstances change overnight - as Ireland found out to their cost in Shizuoka - and so much depends on how squads react and adapt on the run.
Against Scotland, Ireland ended up with a backrow of Chris Farrell, Jack Conan and Niall Scannell. On Saturday night, as they struggled to fight their way back into the game in the closing stages, Ireland were operating with a completely reconstructed back line of Conor Murray and Joey Carbery - in his first outing since August 10th - at half-back.
Garry Ringrose was in the unfamiliar position of inside centre with Jordon Larmour, who has very limited experience of playing in midfield, outside him. Back up scrum-half Luke McGrath was parachuted in on the left-wing, trying to contain Japanese try-scoring machine Kotaro Matsushima while Jacob Stockdale had shifted to full back. Only Murray and Keith Earls remained in their starting positions.
Like Patchell with Wales, there is no way Schmidt would have envisioned Jack Carty starting at No 10 in this crucial game two months ago. Injuries to Johnny Sexton and Carbery changed the picture there.
The Connacht man did well in the opening half, was instrumental in setting up the two Irish tries but, like all those around him, found the going very difficult when Japan got on top as the second half progressed and got sucked into playing the wrong game.
Schmidt now faces the biggest challenge of his coaching career over the next fortnight. After the excellent opening performance against Scotland, everyone was on a high with Ireland in exactly the position the New Zealander had worked so hard to engineer.
Now a total rethink as to how to best resource the matchday squads for the games against Russia on Thursday and Samoa nine days later has taken priority. Ireland need a ten point return from those games to guarantee their place in the quarter-final. As to whether that is against South Africa or New Zealand has become far less of a priority all of a sudden.
There is always a point on tour when a squad faces a crisis. How the players and management react to that is crucial. The response to the mauling Ireland received in Twickenham last month suggests that the character and resilience is there to fashion a recovery.
Cancelling a planned open training session against the Kobelco Steelers, who count a certain Dan Carter amongst their ranks, in Kobe today in favor of a more focused work out against the reigning Japanese Top League champions behind closed doors, offered a further indication of the wagons being circled.
Another was naming Johnny Sexton as captain for the first time in his illustrious career - only the 106th player to do so - despite the presence of other international skippers in Peter O Mahony and Rhys Ruddock in the starting side. Sexton was extremely disappointed to miss out on the Japanese game and now wants to lead the recovery.
As anticipated, Schmidt has rung the changes but has named a strong combination even if eight players start in the tournament for the first time. It is their responsibility to lighten the load on Sexton and grasp the responsibility placed on them to pick up the pieces after what happened Shizuoka.
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