Wayne Pivac has been appointed Wales’s head coach but will not take up the position for 15 months. The 55-year-old New Zealander, who has spent the last four years with the Scarlets, will succeed Warren Gatland after next year’s World Cup, with the Welsh Rugby Union moving early to avoid a frenzy of speculation leading up to the tournament in Japan.

Four of the last six full-time Wales coaches have been New Zealanders, starting with Graham Henry in 1998, the year he also invited Pivac to become one of his assistants at Auckland. He was succeeded by Steve Hansen, the current New Zealand head coach, and Gatland took over after the 2007 World Cup.

“We have secured the best man for the job and we have done so rigorously and decisively to the collective benefit of all involved in Welsh rugby,” WRU chief executive Martyn Phillips said.

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“Both Wayne and Warren and their coaching teams, our international players, supporters and everyone at the Scarlets now have clarity and there is no underestimating the positive benefit to be gained from having the time to plan properly for the future.

“We have avoided the feeding frenzy that can come at the end of a World Cup year and we have been meticulous in ensuring we have someone of the talent, experience, charisma and rugby acumen to do the very best possible job for Welsh rugby. The handover process is something we will plan carefully and commence in detail next summer.”

Hansen and Gatland are the only two Wales coaches in the professional era who have left at a time of their choosing. When the WRU learned two years ago that Gatland would not seek a renewal of his contract in 2019, it started an immediate search for his successor that, with time not an issue, saw them interview 10 candidates and speak to a variety of people in the game all over the world to get their views on what made an outstanding coach.

“It is fair to say that when we started this process, during the Wales tour to New Zealand in 2016, Wayne was not a leading contender,” said Gareth Davies, the WRU chairman. “But I remember having a game of golf in Wellington with someone I will not name who said that he knew a number of players who had worked with Graham Henry, Steve Hansen and Wayne and they rated Wayne the best of them.”

Pivac arrived at the Scarlets four years ago as forwards coach, quickly taking over after head coach Simon Easterby left for Ireland. The region had been struggling but after overseeing a clear-out and bringing in the region’s former international and Lions’ outside-half Stephen Jones to reshape attacking strategy, last year’s then Pro 12 success was followed by a Champions Cup semi-final and another league final, although they lost to Leinster in Dublin on both occasions.

“Having lived in the country for four years, I do not see myself as an outsider but a Welsh coach,” said Pivac, who was on holiday in New Zealand when the WRU chief executive, Martyn Phillips, rang last week to offer him the job. “I would not have put myself through the process if I did not feel it was something I could do and was really passionate about.

“It is an advantage to know regional rugby as I do and I felt comfortable putting my name forward. Warren has had success and that is what I will strive to achieve. People at the Scarlets probably felt we were a wee bit off a couple of years ago but with hard work you can achieve great things. With the talent there is in Wales, as was seen on the recent successful tour to Argentina, we have the opportunity to do well.”

Pivac will remain with the Scarlets next season, giving the region time to find his successor, when he will have nothing to do with Wales. The WRU envisages putting him on the payroll in July next year when he will decide his coaching team and start planning for the 2023 World Cup. He is likely to call on Jones, who will also be a candidate to take over at the Scarlets.

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Pivac, who coached Fiji at international level from 2004 to 2007, has been in charge at the Scarlets for the past four seasons, having initially been assistant to Simon Easterby. Under Pivac the Scarlets won the Pro12 title in 2017 and were pipped by Leinster when defending their title in the recently completed season. They also lost to Leinster in the semi-finals of this year’s European Champions Cup.

Pivac will continue as Scarlets boss until the end of the 2018/19 season and will not officially come under WRU employment until July 2019, with Gatland leading Wales into the World Cup. Gatland’s 12-year reign will make him the nation’s longest-serving and most successful head coach.

“I know I’m following in the footsteps of someone who is held in extremely high regard, not only by the Welsh public but also by the players who have played under him,” Pivac said.

“I will be doing my best to protect the legacy which Warren Gatland, with the help of those players, will inevitably leave behind. It will be an almighty challenge, but one that I’m more than ready for.”