Japan have been the story of this World Cup so far, charming neutrals with a loose, attractive brand of rugby that's carried them into the quarter-finals.

Ireland and Scotland have both been swept aside in Pool A by the Brave Blossoms, who are brimming with confidence.

On this week's RTÉ Rugby Podcast, Fiona Coghlan and Jonny Holland discussed the Japanese rise, with both identifying a strong whiff of New Zealand about their eye-pleasing approach.

"When they're going in that kind of a flow it actually is very similar to the All Blacks," said Holland of a team coached by Kiwi Jamie Joseph.

"I know their coaches will be influenced by that. It's just very nice to watch and I think a lot of attack coaches will be envious of how they get that together because it's very hard to create that flow in a team.

"You see it with Ireland. Once you lose confidence with a loss or something like that the flow isn't there, the passes don't stick. It's very hard to create that culture where the flow is always there. 

"You have to reward it in training. If someone throws an offload in training, you can't give out to them  for throwing an offload if it's the right decision to make. If the execution isn't there but the decision making is right, then you encourage that.

"When Japan make the line break there's a coupe, on the same hymn sheet... trying to get on the end of the next pass before it's even been thrown. It's a positive way to run forward." 

Coghlan shared her admiration for their approach but warned Japan have work to do to ensure this World Cup, and current batch of players, is not a flash in the pan.

"Their basic skills are unbelievable," she said.

"They vary the game up so much and are so exciting to watch. It's not helter-skelter, though it may look it at times. It's controlled, putting kicks in behind or maintaining possession when they need to. They are deserving pool toppers.

"I just wonder if the sustainability is there. Hopefully this tournament will do a huge amount for getting kids playing and have them coming through pathways, which probably aren't as robust as tier one nations.

"What they've done with an incredible bunch of players and coaching staff has been really impressive but a lot of work will have to go into those pathways and structures to try and get kids playing at school if they want this to be sustainable a the next World Cup and beyond."

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