Sunwolves head coach Mark Hammett has been granted compassionate leave and will return to New Zealand following the death of his mother.
Hammett hopes to return to Japan for the Super Rugby franchise's first match of the Super Rugby season, against the Lions on February 27.
"It's a sad day for me and my family on the passing of my mother, Hammett said in a statement, with Filo Tiatia taking charge of the team.
"A lot of my success in life I owe to her. I would like to thank Japan Rugby and the Sunwolves management, players, sponsors and fans for their support at this sad time.
"I will leave Japan to go and support my family and lay my mum to rest. I am hopeful that I can return in time for our inaugural Super Rugby match."