EVEN before yesterday’s stunning victory by Japan against South Africa, the Scotland camp were well aware of the threat posed by Eddie Jones’ team. They cannot have expected the Japanese to have four points in Rugby World Cup Pool B by the time they meet Scotland in Gloucester on Wednesday, but they did – and still do – expect a challenge far tougher than any of the previous meetings between the teams.

Forget the record, was the message from assistant coach Jonathan Humphreys and loosehead prop Alasdair Dickinson. Scotland’s games against Japan have been too few and far between to have any relevance to this match.

Ignore the stereotype, too, they said. The Japanese may once have been literal lightweights – and their nickname, the “Brave Blossoms”, still hints at that past of arduous yet futile effort – but, as that shock triumph over the Springboks demonstrates, they are now a far weightier proposition.

Scotland have improved significantly over the course of their four warm-up matches and they are in far better mental and physical shape now than they were during the Six Nations Championship. But they will have to keep up that improvement if they are to get their campaign off to a winning start against a Japanese side whose tails will now be up, to say the least.

The countries have met twice before in a World Cup, at Murrayfield in 1991, when the home team won 47-9, and in Australia 12 years later, when the Scots won 32-11 in the strength-sapping heat of Townsville. They have met twice since that match, and Scotland won both of those games too – by 100 points to eight at McDiarmid Park in 2004, and 42-17 at Murrayfield less than two years ago.

But, according to Humphreys, even that most recent match will have little or no bearing this time. The former Wales hooker and captain has studied the Japanese and been impressed by the manner in which they have addressed their weaknesses. The scrum, the area where they often struggled most in the past, has been transformed under the guidance of assistant coach Marc dal Maso. The line-out, coached in recent months by former England international lock Steve Borthwick, has also become far more competitive.

“They have improved out of sight in terms of what they’re doing and how they’re going about it,” Humphreys said. “They look very well drilled. I’ve known Steve for a long time and their line-out is certainly representative of him, so we’re expecting an extremely tough challenge.

“In the last 10 years, so-called little teams [have become] very, very strong. They worked out a long time ago what their weaknesses were, and to compete at international level they had to improve in certain areas. And they’ve certainly done that.

“When we played them last time at Murrayfield the scoreline suggested a different game to what it was. It was extremely tough at scrum time in that game. They got two turnovers.

“The days have gone of them being a team that just like to throw the ball around. They’ve kept their identity of being extremely elusive when they attack, but their set-piece is certainly more combative than it’s ever been.”

One of the Scots who has experienced that improvement at first hand is Alasdair Dickinson, the Edinburgh loosehead. “I came off the bench against Japan in 2013 and the scoreline didn’t reflect the manner of the game,” he said. “They’re tough, very fit and physical, and they’ve got good coaches around them. They’re going to be well drilled and they’ll be gunning for us.”

Cotter names his team tomorrow, and Dickinson is likely to be out there in the No 1 jersey. He, hooker Ross Ford and tighthead prop WP Nel form an increasingly formidable front row for Edinburgh, and since South African-born Nel became eligible for Scotland they have begun to replicate their club form at inter- national level.

Of course, with another game against the United States just four days later, Cotter may opt to use his most valuable resources sparingly over the two matches. There is certainly more strength in depth in the squad than has been the case – Dickinson’s main rival in his position, for instance, is Ryan Grant, who toured with the Lions two summers ago. And, according to the Edinburgh player, who made his debut in the 2007 World Cup and competed four years ago, this group is far more able than its predecessors.

“I think it’s a lot stronger,” Dickinson said. “The game’s moved on, so it’s hard to judge exactly, but I think the calibre of the boys we’ve got, especially the young guys coming through, is excellent. We’ve had a really good build-up and you could see that in the warm-up games. We’re in a good place. We’re a humble group of men. We realise Japan will be a massive test.”

Perhaps the biggest test has already come – the one in which players have to settle into the right frame of mind if they are to do their ability justice on the game’s biggest stage. Making no apologies for trotting out the old cliche about taking one game at a time, Dickinson said the key to preparing well was to ignore the magnitude of the tournament and instead deal with each fixture as a one-off.

“A few guys have asked what it was like in previous World Cups,” he said. “It’s hard to describe. You’re in this rugby bubble and there’s this media hype and the build-up has been so long for this – this has been the focus for a lot of players for a long time.

“The simplest way to put it is that you just have to think about one game and then, whatever happens, you just progress to the next game. You can’t think about the bigger picture, that’s what I say anyway, or else you get engulfed by the whole lot.”

Japan managed not to be engulfed by the magnitude of the occasion yesterday. It is now up to Scotland to exhibit the same sang froid on Wednesday.