Japan rugby head coach Jamie Joseph on Thursday urged the Brave Blossoms to forget about their 2015 World Cup heroics and focus on rebuilding for the 2019 tournament on home soil.

"What's important now is that we leave the World Cup behind," Joseph said at Prince Chichibu Memorial Rugby Ground, as he laid out his plans for the year ahead. "We can't keep on talking about 2015. I'm not sure that any coach in any other team talks about things that happened two years ago in sport."

New Zealander Joseph took charge of the team in September last year, almost a year after the Brave Blossoms had shocked the world by beating South Africa, Samoa and the United States at the World Cup in England under previous coach Eddie Jones.

Joseph had less than three months to familiarize himself with Japan's players before picking a November squad to face Argentina in Tokyo, and Georgia, Wales and Fiji on a European tour.

Complicating matters was the fact that several World Cup stars such as Ayumu Goromaru and Michael Leitch were injured or had ruled themselves out of contention due to their heavy workload.

But Japan put in a respectable performance nonetheless, losing 54-20 to Argentina before beating Georgia 28-22 in Tbilisi, then coming close to a famous result in a 33-30 loss to Wales in front of more than 70,000 in Cardiff before crashing 38-25 to Fiji in France.

"I guess for me really the first three months before the November tour was quite hectic being the only coach," he said. "When I first arrived in Japan, rugby was very popular after a very good World Cup. Expectations were very high.

"But the reality of those experiences was the national team had been in limbo for eight months and half the team had retired from international rugby. I was set a task to select a team by myself because my coaching team were either involved with other Super Rugby teams or other company teams. It was difficult but I think we made some good steps in the right direction."

Now Joseph is preparing for his first full year on the job, with Japan set to play Romania and Ireland (twice) on home soil in June before facing Australia at home and France away in November.

"In November, we've got two test matches against two quality sides," he said. "That's better for us — to play tougher teams than to play sides as strong as us or weaker than us — for our own development."

Joseph will also play a hands-on role with Japan's Sunwolves Super Rugby franchise, coaching the players who have not been chosen for the squad while the team is overseas preparing for matches. Joseph's coaches will also work with up-and-coming university players.

"This is obviously going to give me a better understanding of the type of ability we have because from now on we will be exposed to nearly 70 players playing in Japan before we select a team to play our test matches in June," he said.

"It's time to roll the sleeves up and do some coaching and develop our game in preparation for June, in preparation for November, but ultimately for the World Cup in 2019."

Joseph is also casting his net wider than just players who were born in Japan.

"Every one of the foreign players with the Sunwolves, apart from one, will be eligible to play for Japan by 2019," he said. "That was one of the rules we made when we were looking at foreign players."

Joseph stressed that he sees the Sunwolves as the driver for Japan's 2019 World Cup preparations, and warned overseas-based stars such as Goromaru and Leitch that their presence on the team will be required somewhere down the line.

"There are no hard rules," he said. "I don't feel I'm in a position to exclude players from playing for Japan if they are the best players because they're playing for other teams. Sometimes it's the best thing to get out and experience new environments and coaches.

"But ideally, we would have our players together. In a perfect world, before the World Cup, certainly in 2019, the players we will be looking at will need to be involved with the Sunwolves. In 2018, I think we need to move in the same direction. But with professional rugby and contracts, it's not always easy."