Japan coach Jamie Joseph said three years of preparation had gone into his team's World Cup Pool D decider against Argentina in Nantes on Sunday.

The Japanese made the quarterfinals of the last World Cup, on home soil, in 2019, famously taking the scalps of Ireland and Scotland in the pool stage.

Although they were knocked out by eventual winners South Africa, Joseph and his players were hailed as having turned the tide for rugby in Japan.

There is no denying, however, that Japan, who also won three pool games in 2015 including against the Springboks but failed to advance to the quarters, have not recently posed the same threat to teams.

In France this time around, they overcame Chile 42-12 before losing 34-12 to England and then beating Samoa 28-22.

That set of results has set up a straight shoot-out with Argentina for second spot in the pool and a place in the quarterfinals, likely to be against Wales in Marseille.

"It's a big game of footy," Joseph said.

"We've been preparing for the last three years for this game of rugby, so we're looking forward to it."

Joseph, who played for the All Blacks before switching allegiance to Japan, added: "We've got to make sure it's not our last game.

"There have been a lot of close games, especially in this pool.

"What we've said to our team, our players, is that if we can get into a position where we have got a grand final which is for us against Argentina on the weekend, then we're halfway there.

"We've just got to go play 80 minutes of rugby and make sure we play that rugby the best we can and play our style of rugby."

'WIN THE MENTAL BATTLE FIRST'

Joseph said there were "no surprises" as Argentina counterpart Michael Cheika picked a strong side for the game.

"It's like a quarterfinal or semifinal for us already because the losing team goes home," he said.

"The guys are really confident, I'm confident as a coach that our guys will put in a really good performance on the weekend.

"If we create the right pressure at the right time, I'm confident that we'll win the test match."

Japan winger Kotaro Matsushima added: "As a team, there's definitely going to be pressure, but we don't want to be passive and we need to put pressure on them in every situation."

Matsushima, one of the stars of the 2019 World Cup, insisted that Argentina's recent wavering form would not count as much as the right mental approach come Sunday.

"Perhaps due to pressure, they don't seem to be clicking at the moment, but because it's a do-or-die thing, it's going to come down to our will to win the game," he said.

"They are a dangerous team with momentum, but we are the same when we have the momentum. We don't know who's going to have it, but we want to win the mental battle first."