This comes hot on the heels of Lima Sopoaga, the 16 test All Blacks first five-eighth, leaving in his prime – after one final season with the Highlanders – on a mega deal worth $1.13 million (NZD) per year with Coventry-based Wasps.
Read more: Lyon confirm signature of Charlie Ngatai
On the face of it Tamanivalu's exit seems surprising after reviving his prospects on the edge with the Crusaders last year. His comeback to the All Blacks, a year on from his first three tests in the midfield, saw him impress against the Barbarians and French XV last November.
Dig a little deeper, though, and it quickly becomes apparent the outside backs will be one of the most hotly contested areas in the All Blacks.
Like Sopoaga, Tamanivalu may be keen to strike while his value is high rather than waiting to push for a place in the World Cup squad. Born in Fiji, he may also have family back home to support.
With Israel Dagg, Ben Smith, Jordie Barrett and Nehe Milner-Skudder all due to make their anticipated returns this season, and Rieko Ioane and Waisake Naholo proving their test credentials, Tamanivalu could easily slip down the pecking order, no matter how compelling his form.
While not a natural wing, Tamanivalu's gifted physical attributes made him a force after shifting from the Chiefs to the Crusaders. The 25-year-old is just beginning to showcase his rounded abilities, and now that talent may be lost to offshore riches.
Ngatai may not garner the same headlines as others but he is probably the biggest loss.
Unlike other areas, depth in the midfield, particularly at No 12, is not stacked, and someone of his experience and genuine class takes many years to fully develop.
Unfortunately for Ngatai, who has captained New Zealand Maori, the Chiefs and Taranaki, repeated concussion robbed him of the chance to grab his opening with the All Blacks, restricting him to one test in Samoa in 2015.
Fully fit he could easily have reached double figures by now. It has been a case of what might have been.
Successive head knocks threatened his career last year and at 27, it makes sense for him to cash in while he can. But at his best, Ngatai's range of skill is as good as any second-five.
- Additional reporting by Liam Napier
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