Tokyo - Scotland's rugby chief insisted he won't allow his side to become "collateral damage" at the Rugby World Cup as he fights off moves to cancel Sunday's decisive pool clash with Japan over an incoming typhoon.

World Cup organisers have already taken the unprecedented decision to axe Saturday's matches between England and France and New Zealand and Italy with Typhoon Hagibis poised to hit Japan's east coast.

Scotland's Pool A match against Japan in Yokohama on Sunday is also under threat from the extreme weather, with a decision on whether it goes ahead set to be taken on the morning of the game.

Assuming Ireland manage at least a losing bonus in their final pool match against Samoa on Saturday, the Scots will need a victory over Japan to have a chance of reaching the last eight.

But if their game is called off and, under tournament regulations, declared a 0-0 draw, the two points Scotland will then receive won't stop them being eliminated.

"My view is that we're not going to let Scotland be the collateral damage for a decision that was taken in haste," SRU chief executive Mark Dodson told BBC Radio Four's Today programme on Friday.

"I think there's alternative (venues) around Japan."

World Rugby has insisted the only two options are playing the Scotland-Japan match as scheduled, or cancellation.

But Scotland dispute this interpretation of the rulebook, arguing a 'force majeure' clause allows for weather-affected pool games to be rescheduled, as can happen in the knockout phase.

Dodson said that while the question of whether the match took place on Sunday was now a "purely meteorological issue", and public safety was the priority, cancelling the fixture would wreck the "sporting integrity" of the tournament.

"World Rugby seem to be determined to stick to its plan that the match is either played on Sunday or indeed it is cancelled, and to have it cancelled and have our ability to progress from this group put at peril, we believe is absolutely unacceptable," added Dodson, who warned legal action remained a possibility.

"World Rugby is pointing us back to the participation agreement. We've had legal opinion -- from a leading QC (senior lawyer) - that challenges World Rugby's interpretation.

- 'Play 24 hours later' -

"We don't know that (it's too late) -- we have to challenge it. This is about the game and rugby supporters across the world are absolutely astounded at this rigidity from World Rugby."

"The common-sense approach to this is to play the game 24 hours later in perfect safety where we can make sure that the pool stages are completed," he added.

Meanwhile, Scotland coach Gregor Townsend dropped captain Stuart McInally to the bench and installed experienced scrum-half Greig Laidlaw as skipper when he named his team on Friday.

Fraser Brown starts at hooker instead of McInally, yet to find his best form in Japan.

Brown, who started at flanker in Wednesday's 61-0 hammering of Russia, is one of three Dark Blues players who will be kicking off for the second time in four days together with wings Tommy Seymour and Darcy Graham.

Scotland, who started this World Cup with a woeful 27-3 loss to Ireland, are up against a Japan side who've won all three of their group games so far.

"The opportunity to face the hosts in such a decisive pool match will be a unique occasion and should be a great spectacle," said Townsend.

"Games of this magnitude don't come around very often in a playing career so we will be giving it everything to make sure it is a memorable match," he added.