Ngarimu has played for the New Zealand Divisional XV (the predecessor to the New Zealand Heartland XV), Maori All Blacks (then New Zealand Maori) and Hawke's Bay. The current coach of Poverty Bay said his assistant coach role was an opportunity to contribute to a proud tradition of grassroots rugby.
"These players fit their training around fulltime jobs and are loyal to their provinces, gaining immense pride from representing their home town. For some it will be the pinnacle of their rugby career and for others it's a stepping stone to higher honours.
Either way, it's a fantastic team to be involved with, and I have very fond memories of my own experience in the New Zealand Divisional XV."
NZ Rugby general manager community and provincial union rugby Brent Anderson said the two coaches had the depth of experience and skill required to ensure the team would be well prepared and competitive.
"The selectors were impressed with Keenan and Ngarimu. They will need to be able to pull together the team quickly and only have a short space of time to make sure they are humming and ready to take on Marist and the Australian Barbarians. We are confident these coaches are right for the job."
The New Zealand Heartland XV play New Zealand Marist for the McCrea Cup annually. The Australian Barbarians will be selected from non-Super Rugby contracted players playing in the National Rugby Championship, which kicked off last week.
The tour dates and locations are yet to be confirmed, though the Australian Rugby Union did announce last week that it would be a two-match series in Levin and Wanganui. NZ Rugby would only state that all games will take place in Heartland provincial unions in early November.