Ireland overpowered Japan 35-13 on Saturday for their second straight win over their hosts to finish with a perfect record in their three-game summer tour.
Joe Schmidt's second-string side looked on course to rack up 50 points for the third successive match -- the first of which was against the USA -- as they ran in four first-half tries in Tokyo.
The signs were ominous for Japan's "Brave Blossoms" when Garry Ringrose raced clear to score under the posts and flanker Josh van der Flier wriggled over in the corner in the first 10 minutes.
Bulldozing tries from Kieran Marmion and stand-in skipper Rhys Ruddock further stretched the lead for Ireland, the bulk of whose regular players are on British and Irish Lions duty in New Zealand.
Japan's sole glimmer of hope had been Kotaro Matsushima's fine try on 24 minutes but after trailing 28-8 at half-time, the 2019 World Cup hosts offered significantly more resistance after the interval.
Akihito Yamada tiptoed down the wing to register Japan's second try, while Ireland narrowly avoided going scoreless in the second half thanks to Sean Reidy's late effort.
Fly-half Paddy Jackson unerringly converted all five tries for Ireland, who crushed Japan 50-22 last weekend and also broke the 50-point mark against the United States in their opening tour game in New Jersey.
"We knew after last week Japan would bring a new level of intensity and test us," said Ruddock.
"They certainly did that. It was a really tough game and credit Japan for the pace and tempo they played at."
Japan, who warmed up for the two tests against Ireland by beating Romania 33-21 earlier this month, were once again given a lesson in possession rugby by a team they will face in the pool stage of the 2019 World Cup.
"In terms of attitude we 100 percent left everything out there," said Japan captain Michael Leitch.
"Ireland are one of the top four teams in the world and the way they keep the ball and the intelligence they play with are things we need to learn from. Tactically we also need to sharpen up as we build to 2019."
Japan had never beaten Ireland and the last time they met before last weekend was in 2005.
The Asian champions have made real progress since then, shedding their tag as World Cup pushovers by winning three games at the 2015 tournament under Eddie Jones, including a stunning upset of South Africa.
But they never seriously threatened Ireland and Japan coach Jamie Joseph cut a frustrated figure as his players committed a string of elementary handling errors.