Scott Robertson signs extension with Crusaders, NZ Rugby

The All Blacks coaching field appears to have narrowed once more, after Crusaders coach Scott Robertson opted to re-sign with the two-time defending champions for a further two seasons.

Robertson's decision to remain in Christchurch means current All Blacks assistant coach Ian Foster looks increasingly likely to succeed Steve Hansen when he steps away after this year's World Cup.

Robertson had already signalled his interest in coaching the All Blacks but had also indicated he may be tempted by a move overseas should he be deemed not ready to take on the top job.

But he will instead continue his coaching development in Christchurch where he will guide the Crusaders through a potentially tricky transition period should the likes of Test skipper Kieran Read, veteran centre Ryan Crotty and lock Sam Whitelock decide to join the back-rower Jordan Taufua and prop Owen Franks in moving on after the World Cup.

Given Robertson's deal is with New Zealand Rugby and not just the Crusaders, there is no reason why he couldn't foreseably still be awarded the All Blacks job. But such is his affection for the Crusaders and the fact that Foster seems a ready-made replacement for Hansen, and has his mentor's endorsement, a move to the Test setup for Robertson beyond 2021 looks far more likely.

"I'm grateful for the opportunity to continue to lead a group of incredible players, alongside a coaching staff and management group who are passionate about what we do and the organisation we represent," Robertson said.

"My family and I are really settled here and when my wife Jane and I talked about it, this is ultimately where we wanted to be. I had already signalled my commitment to New Zealand Rugby and this 2019 campaign with the Crusaders, but this announcement ensures I can now focus on the task at hand and move forward with certainty around my coaching future.

"It's a huge honour to lead this team and I'm thankful for the support I have been shown by New Zealand Rugby, the Crusaders Board and the team, in extending my time with the club."

With Joe Schmidt already indicating he will take a year off from coaching after his contract wraps up with Ireland, Foster is the hot tip to succeed Hansen. Current Wales coach Warren Gatland is also believed to be in contention but both he and current Glasgow boss Dave Rennie were seen to be behind Robertson on the list of potential replacements.

It could be that Robertson joins the national set-up as an assistant to whomever succeeds Hansen, and then graduates into the top job at later date from there.