Mitchell will step down on January 31 and the NZR Board has voted for Dame Patsy, the former governor-general of New Zealand, to take over.

Farah Palmer and Bailey Mackey have been appointed deputy chairs, a role Palmer already held.

Dame Patsy has only been on the NZR Board since April, but can fall back on the experience of a long legal career before being the monarch's representative in New Zealand for five years.

"It is an absolute honour to be elected to the position of chair at such a pivotal and exciting moment for rugby in Aotearoa," Dame Patsy said. 

"I would like to thank Stewart for his long service to the Board and his leadership over the past two years as chair. 

"He has left rugby in a strong position to grasp the opportunities in front of us and with a diverse and skilled Board I could not be more excited about the challenges ahead."

Mitchell's tenure as chair, which began in May 2021, has included Silver Lake, a private equity firm, buying a minority stake in NZR for NZD200 million (£104 million/$127 million/€121 million).

It has also been defined by the COVID-19 crisis, which hit rugby in the country hard and contributed to the break-up of club competition Super Rugby.

NZR and Rugby Australia earlier this month reached an agreement for Super Rugby Pacific, a new version which has dropped South African, Japanese and Argentinian teams, to continue until 2030.

NZR also hosted the women's 15-a-side Rugby World Cup - which the host nation won - this year, following a year-long delay brought about by the global health crisis.

New Zealand won the women's rugby sevens gold medal at last year's delayed Olympics and came second in the men's tournament. 

"On behalf of NZR, I would like to say thank you to Stewart," NZR President Max Spence said.

"He has guided the Board through some extraordinary times and always done so with passion and dedication. 

"He has been a champion for diversity and a driving force behind many of our major milestones as an organisation in recent years."

Deputy chair Palmer is now a professor, following a glittering playing career which included captaining New Zealand at three Rugby World Cups.

Palmer was inducted into the World Rugby Hall of Fame in 2014 and has served on the New Zealand Māori Rugby Board since 2007.

Mackey has a background in broadcast production and joined the NZR Board in 2020.

NZR is among the most influential of World Rugby's members and New Zealand has three officials on the World Rugby Council.

NZR is additionally a founding member of South Africa, New Zealand, Australia and Argentina Rugby, known better as SANZAAR.