Gatland will likely resign as Wales coach in 2019, and with 2021 tour of South Africa not as challenging, he may decide to move on from Lions assignment to take over his native New Zealand side - if offered job one day.
Lions form primes Warren Gatland for possible stint as All Blacks coach
The British & Irish Lions lost three series in a row, up until the appointment of Warren Gatland in 2013. Continue on like that for much longer, and the whole concept would have been consigned to the dustbin.
On his watch, they have so far won one series, and drawn the other. Pride in the Lions, it is fair to say, has been restored by a New Zealander who seldom makes a decision without putting at least half his public offside.
He dropped Brian O’Driscoll. He persisted with Alun Wyn Jones. He benched Maro Itoje. He picked a load of random replacements, based on nothing more meritorious than the fact they were nearby at the time. Then got spooked, and did not let them play, anyway.
And yet his record as head coach of the Lions reads played six Tests, won three, lost two, drawn one.
It is a significant feat. So why should he not consider a third go at it, in South Africa in four years’ time?
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Whatever happens, this tour, Gatland’s homecoming in New Zealand, was the summit series he will face. Australia were, to all intents and purposes, well beaten in 2013.
And it seems unrealistic at present to think the Springboks could possibly pose a bigger challenge than New Zealand did this time around. South African rugby will have to change out of all recognition from the state it is in now if they are going to.
So Gatland will surely believe he could advance his positive Lions record if he was in situ then.
He will be 57 by 2021, and his circumstances might be significantly altered. He will not be taking a sabbatical from coaching Wales, as he has done to lead the past two Lions tours.
His contract with Wales ends after the 2019 World Cup, and he says he will not be staying on in Cardiff.
A year off, and then a year spent with the Lions as his sole focus seems to be a perfectly neat fit.
There seems to be only one impediment. For all that he has become the ideal coach for the Lions, the lure of the All Blacks job once Steve Hansen finishes would surely be too much, were it offered to him.