DUBLIN: Irrespective of how Joe Schmidt's time with Ireland ends in the coming weeks, the New Zealander will still depart as the national team's greatest ever coach.
Since taking charge in 2013, he has brought home three Six Nations titles - one a Grand Slam - to a country that had won one in the previous 28 years.
Wider afield, he pushed Ireland to truly mix it with the best of the southern hemisphere for the first time, including a maiden win over the All Blacks that had eluded the men in green for 111 years.
For good measure, he notched up a second victory over the world champions last year, the first on Irish soil.
If Ireland cannot quickly rediscover the form that earned them that success, however, Schmidt could be yet another Irish coach unable to lead the perennial World Cup underachievers past the last eight of the tournament.
That would be likely to rankle with the obsessive former school headmaster for some time while he earns some well-earned time away from the game come November.
Japan might just be the greatest test for a coach whose impact on Irish rugby was instantaneous when he arrived nine years ago and led Leinster to two European titles in his three years.
Schmidt has overcome setbacks before in his time with Ireland, of course, putting the 2015 World Cup quarter-final exit and disappointing Six Nations campaigns that followed aside to romp home to the Grand Slam during the near faultless 2018.
He has far less time to turn around a disjointed 2019 campaign which began with a poor Six Nations defence and led to the Irish Times headline: "Maybe Joe Schmidt is on the verge of being burnt out".
His selections are also being questioned by some analysts for the first time after he picked the relatively untested Jean Kleyn to travel to Japan ahead of Devin Toner, the go-to lineout jumper for much of his time in charge.
Ireland great Brian O'Driscoll did not call Schmidt the best coach he played under for nothing, though, and the country that has wholly adpoted the dual citizen as one of their own would not want anyone else figuring a way through this one.
For a man long touted as the next coach of his native New Zealand before he indicated he intended taking a break from the game, adding another first and reaching the promised land of the last four would be a deserved way to start that down time.
(Reporting by Padraic Halpin, editing by Nick Mulvenney)