Scotland do not have to sparkle from the off at the World Cup so long as they can find a way to leave Ireland dazed in their tournament opener, according to hooker Fraser Brown.

Gregor Townsend's team could not have asked for a harder start as they take on the world's number one ranked side a week on Sunday.

And that is why he reckons the Scots will be more than content to grind their way past Joe Schmidt's men at Yokohama's International Stadium.

"World Cups are definitely all about momentum," he told the PA news agency. "They key is being able to start the competition well enough to win games but not to peak in that first week.

"The competition is potentially eight weeks long and if you're peaking in week one then it's a long time to sustain that.

"You have to try to build your performances as you go but still play well enough to make sure you're picking up results."

Schmidt's team opened themselves up to criticism after crashing 57-15 to England at Twickenham last month.

But they responded to that set-back in impressive style with home-and-away wins over Guinness Six Nations Grand Slam winners Wales.

They way they took care of Warren Gatland's team will be a real concern for the Dark Blues, who have won just once in the two nations' last seven meetings.

But Brown does not believe a Scotland victory would count as an early World Cup shock.

He said: "It won't be a surprise (if we win).

"The last couple of years, Scotland-Ireland games have been very physical, very intense.

"The set-piece battle will be huge, so will the battle of the defences. Ireland will hold onto the ball for long periods of time so slowing them down at the breakdown and getting our defence in place will be key.

"But we're a good enough team to compete with them and win."

Brown was handed a ticket to Japan despite having not featured at all during the Scots' four-game warm-up series after injuring his foot during Glasgow's PRO14 final defeat to Leinster.

The 42-cap front-rower is relieved to make the cut but insists he is not using the pain of Scotland's World Cup exit four years ago - when referee Craig Joubert's error cost them a semi-final slot as Australia sneaked through at Twickenham - to get him in fired up for action.

"It was a relief to get the call because, with me not having been available for any of the warm-up games before the squad was announced, you just never knew what the coaches were thinking," admitted the 30-year-old, who will most likely play deputy to skipper Stuart McInally in the number two jersey.

"Back in May when I got injured I sat down with Gregor and the medical staff and drew up a plan around realistic time-frames and what I'd be able to do.

"It was just about making sure I ticked the boxes along the summer to make sure I was in a good place.

"It's always a big worry because you're not showing what you can do in games but I'm relieved to be here now and fit.

"What happened in 2015 is not a huge driving force for me personally if I'm being honest.

"As a squad - plus me too - we're in a completely different place to where we were four years ago.

"Those kind of things can happen in any game.

"The most important things for me now is that I'm back fit and that I play well when I get an opportunity.

"You can't affect the randomness of what happens in a game of rugby sometimes. All you can do is try to be as consistent as possible in how your team performs."

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