Fresh from winning a fifth straight Asian Five Nations title last month, Japan turn their attention to the Pacific Nations Cup which kicks off on Tuesday.
The hosts face Fiji while Tonga play Samoa - with both matches in Nagoya - in the opening round of the four-nation tournament.
New Japan coach Eddie Jones has pledged all-out attack as Japan launch the defence of their Pacific Nations Cup crown. But they must contend with a wounded Fiji and a determined Tonga intent on revenge.
Jones, a former Wallaby coach who took over the Brave Blossoms in April, admitted they had plenty of luck in winning their first Pacific Nations Cup title last year after a 24-13 victory over Fiji away.
It was Japan's first triumph over Fiji in six years but Jones attributed it to a "world-record number of sin bins" for the Flying Fijians, who finished the match with only 12 men.
Jones, who led his native Australia to the 2003 World Cup final, said Japan would stick to his brand of attacking rugby, as he keeps one eye on steering the team into the top 10 by the 2015 World Cup in England.
Japan, currently ranked 14th in the world, host rugby's premier event in 2019.
"We're going to put so much pressure on Fiji by attacking with the ball and when we don't have the ball we'll also attack them," said Jones.
"These are the games we must win."
"We're going to play our game so we're not too worried about Fiji," he added. "That's the way we have to be to develop and succeed."
But Fiji, ranked just two places below Japan, are out to settle a score with the Brave Blossoms.
"It is a huge responsibility for the boys to turn the tables on the Japanese on their home soil in front of their home fans," new head coach Inoke Male told The Fiji Times.
"One of our main aims right now is to better our rankings," added Male, who has called up Fiji-based players and Sevens stars to fill in for the absence of some overseas-based players.
"We have prepared well and the team bonding is strong."
Tonga and Samoa, ninth and 10th in the IRB world rankings, face up in the other clash in the opening round of the round-robin tournament.
Samoa, under new coach Stephen Betham, have axed a number of senior players including skipper Mahonri Schwalger as they strive to grab back the title they won in 2010.
Prior to that, New Zealand dominated the Pacific Nations Cup through the Junior All Blacks and the New Zealand Maori when its initial format was as a five-nation competition in 2006.
Tonga, who beat eventual finalists France but failed to qualify for the knockout phase of the 2011 World Cup, will be desperate for revenge after narrowly losing out to Japan for the Pacific Nations Cup last year.
Japan scored their fourth try against Fiji in injury time for one bonus point to finish level on points with Tonga.
But the title went to Japan by virtue of their 28-27 win over Tonga earlier in the tournament. It was the fifth time in a row that they had lost to the Japanese.
Pacific Nations Cup fixtures (all times GMT):
June 5: Samoa v Tonga (08:10), Fiji v Japan (10:10) in Nagoya, Japan
June 10: Fiji v Samoa (03:10), Japan v Tonga (05:10) in Tokyo, Japan
June 17: Samoa v Japan (05:10) in Tokyo, Japan
June 23: Fiji v Tonga (03:40) in Lautoka, Fiji