Eddie Jones has urged Japan to keep faith in him despite lacklustre results that have included several heavy defeats since he returned as head coach almost a year ago.
Japan have won four games and lost seven since the Australian took over in January, and were beaten by 40 points or more by New Zealand, France and England.
Jones told reporters late Tuesday after returning from Japan's tour of Europe that there was "no magic solution" but said he was confident that his team would improve.
"They're the sort of experiences this team needs," Jones said of the tour, which ended with a 59-14 thrashing by his former team England at Twickenham on Sunday.
"I know you're all sitting there thinking we got beat by 50 points but they're games we need to actually learn (from).
"The big challenge now is how quickly we can learn," he added.
The 64-year-old Jones, who first coached Japan in 2012-2015, has blooded a glut of new players including a full-back who is still at university.
The Australian said his players' inexperience had "shown up at crucial times in games" but believes Japan can become "the best attacking team in the world".
"There is a gap between where we are and where we need to be, and we just need to keep working," said Jones, a colourful and controversial character.
"The only thing that's going to get us there is hard work, persistence and then consistency in selection."
Japan have signed partnership agreements with both Australia and New Zealand, meaning they will play regular test matches against them over the next few years.
Jones returned to the Japan job six weeks after walking out on Australia following a disastrous year-long stint in charge of the Wallabies.
He had repeatedly denied reports he was set to take the Japan post for a second time.
Jones has also come under renewed scrutiny in recent weeks for his time in charge of England, with former scrum-half Danny Care calling him a "tyrant" and a "despot" in his autobiography.
Jones said he was abused by a fan at halftime of Sunday's game in his first return to Twickenham since being sacked in 2022.
He took England to the World Cup final in 2019, where they lost to South Africa.