Stakes are high as Townsend gets up to speed with Scots
When Gregor Townsend told his employers in the middle of 2016 that he wanted to take charge of Scotland, he was, at 43, still in the relatively early stages of his coaching career.
He might easily have acquired a lucrative post elsewhere for a time before turning his attention to the national team.
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But the then coach of Glasgow Warriors - a team owned by the Scottish Rugby Union - was convinced there was a significant opportunity at that point, which might have disappeared had he waited: the lure of working with what he believes is a uniquely talented generation of young players.
Three years on that belief remains. Townsend, who had to wait for Vern Cotter's contract to expire before assuming office in the spring of 2017, now has what may be his only chance to make the most of that talent - and to convert his own promise as a national coach into reality.
It was the impact he had on Glasgow, where he won the Pro12 title in 2015, that made Townsend hot property in the eyes of the SRU.
The former fly-half's own attacking instincts brought out the best in players such as Stuart Hogg and Finn Russell, and the team continued the steady progress begun by his predecessor, Sean Lineen: a semi-final defeat in the new coach's first season, a loss in the final in his second and then that title in his third.
Hogg turned 27 in June and Russell will do so later this month, so both should still be around in four years.
The rising stars Darcy Graham and Blair Kinghorn, both 22, could easily have two World Cups ahead of them after this one.
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But the tighthead Willem Nel, the cornerstone of the pack, is 33.
So is the scrum-half Greig Laidlaw (pictured), whose game management is the most astute in the squad by some margin. So some reconstruction of the side will be required in relatively short order.
After a year in the post, Townsend signed an extension that means his contract now runs until 2021. There is no guarantee that he will be offered a new deal then, or even that he will want to extend his tenure beyond that point.
So the stakes are high in Japan. Townsend is the most inspiring coach Scotland have had this century, both in terms of his individual character and the rugby his teams play.
But, faced with a pool that includes the host nation as well as Ireland, Samoa and Russia, he also runs the risk of becoming only the second Scotland coach, after Andy Robinson eight years ago, to fail to qualify for the quarter-finals.
Not that Townsend has ever been afraid of risk.
His attitude as a player was testament to that, as is the style which he has encouraged his teams to adopt.
His team selections, too, can be adventurous, and at Glasgow, the at times perplexing permutations he would make in his starting lineup from one week to the next gave rise to the phrase "the Toony Tombola".
But the implication that his choices were randomly generated could hardly have been wider of the mark. So too the more polite suggestion that there was method in his madness.
At most, there was - and is - a hint of madness about his method: in common with other coaches, he likes to have a touch of unpredictability within his side.
A related accusation sometimes levelled at Townsend is that he is an otherworldly aesthete, a sporting idealist who either cannot or will not get to grips with the harsh realities of the game.
The charge dates back to his playing days, when his attacking instincts were at times as unpredictable for his own teammates as for the opposition. It was aired again in the wake of last month's five-try defeat in France, when his avowed intention to play the fastest-tempo rugby in the world came in for criticism for its supposed naivety.
High-speed rugby is not a virtue in itself, and cannot disguise the obvious deficiencies in this Scotland side.
The significant discrepancy between the team's home and away form is one such inadequacy, even if Georgia were summarily dispatched 44-10 in Tbilisi, while the other is its relative weakness when up against the most fearsomely physical of opponents.
But the coach has never argued that the high-tempo game is a panacea, nor that it should be adopted merely because it is more entertaining. Instead, he sees it as Scotland's best - perhaps only - chance of beating the top teams in the world.
To an extent that is making a virtue of necessity. This Scotland squad does not have the abundance of hypertrophied specimens available to teams such as France and South Africa, and that limits the range of viable gameplans available to the coach.
But he has certainly never lost sight of the pressing need to improve the defence, and it was notable at the Scotland squad announcement that he emphasised its virtues in that respect, with the omission of Huw Jones largely down to that factor.
Under Cotter four years ago, Scotland came within minutes of reaching the World Cup semi-finals for the first time since 1991.
Under Townsend, they might do something similar - or they might fall flat on their faces and lose to both the Irish and Japanese. Either way, their games will be compelling viewing.
Sunday Indo Sport