The move follows weeks of speculation that the reigning Super Rugby champions had offered an initial two-year contract for him to become assistant head coach to Scott Robertson.

In a statement released this morning, Racing confirmed that despite being under contract until 2019, the club "did not want to deprive one of its faithful servants of a great opportunity", and that the 40-year-old would be released in December.

Découvrez le communiqué de Presse du Racing 92 concernant Ronan O'Gara, entraîneur Adjoint dans le staff technique. https://t.co/ujUwojkLqN pic.twitter.com/sqn1mc9DgL

— Racing 92 (@racing92) November 22, 2017

A move to New Zealand’s south island would clearly bring about some upheaval for O’Gara’s family, his wife Jessica and their five children, but in a recent Irish Examiner column, he expressed the view that he still has a significant amount of learning to do as coach in different parts of the world before he is ready to be considered for a No 1 coaching role - or a return to Ireland.

The Christchurch-based Crusaders have won a record eight Super rugby titles and are regarded as the premier club team in the world game.