Chris Rattue: Steven Luatua departure a massive blow for Blues

Steven Luatua's decision to quit New Zealand rugby for Bristol is a big blow for the Blues - he would have been central to Tana Umaga's plans to revive the long-suffering giant.

A jubilant Bristol made the announcement overnight, with Luatua to join them for the 2017/18 season. There was no official word out of New Zealand Rugby this morning. There was no detail on the length of the contract.

It's another disaster of sorts for the Auckland-based Super side, who lost another rising linchpin Charles Piutau when the young test back quit for Ulster a couple of years ago.

While Luatua was seen as a Blues mainstay, the athletic loose forward's test career was far less certain after a patchy 15-test stint since his debut in 2013.

But he was still a potentially classy option for the All Blacks and presumably remains an option to face the Lions if needed in the massive mid-year series unless the All Blacks choose to snub him, as occurred with Piutau when it came to World Cup time.

The 25-year-old Luatua, who will join the Pat Lam-coached English club for the 2017/18 northern season, represents a significant loss for New Zealand rugby because he is a current test candidate who should be in the prime of his career.

It's also a blow to New Zealand rugby morale, as it fights a never ending battle against rich overseas clubs.

Luatua may have struggled to make a powerful impact in tests, but he had plenty to stay for. All Black great Jerome Kaino turns 34 this year meaning he is far from certain to be part of a bid for a third consecutive World Cup victory. Luatua had the added bonus of being able to cover at lock.

The problem for Luatua is that he lacked the physical grunt that Kaino has brought to the No. 6 jersey. Like Highlander Elliot Dixon, he hasn't displayed immediate test class when given his chance.

Maybe Luatua read the writing on the wall, with Liam Squire at the head of the test queue to replace Kaino and others such as Ardie Savea and Brad Shields in the hunt. And the All Black locks are so athletic these days that they are capable of having stints at blindside during matches.

Bristol have trumpeted Luatua's signature as "among the most significant signings in the club's recent history".

As part of Bristol's announcement, Luatua said: "I have a fantastic relationship with Pat [Lam] and I enjoyed working with him at the Blues. I'm looking forward to taking on a new challenge with Bristol and contributing to the long term vision of the club.

"Bristol Rugby is one of the most ambitious clubs in the UK and that's backed up by a really passionate fan base. I've heard great things about the environment that is being built there and the plans in place, so I can't wait to get started in the summer."

Steven Luatua

Age: 25
Auckland games: 31
Blues: 63
Tests: 15