The Sunwolves will have a fourth head coach in four seasons of Super Rugby after Jamie Joseph announced he'll stand aside in 2019.
Japan national coach Joseph will instead concentrate on preparing the Brave Blossoms for next year's World Cup, which they will host.
He will play a part in appointing next year's Sunwolves coaching staff.
Tony Brown will be favoured to be promoted from assistant coach to head coach, potentially mirroring the same transition that took place at New Zealand's Highlanders in 2017.
Joseph revealed the change at a news conference in Tokyo before the launch of events to celebrate one year to go to the World Cup.
The 48-year-old New Zealander succeeded Filo Tiatia as head coach this year and failed to prevent the Sunwolves picking up the wooden spoon for the second time in their three-year existence.
They also finished last in their inaugural 2016 campaign under Mark Hammett.
The Sunwolves, who have won six of 46 games, look set to struggle again next year.
Josephy revealed a number of his Japanese international players on the Sunwolves roster will sit out the opening rounds of Super Rugby to ensure they are peaking for the World Cup.
