Away from plotting to end each other's tournaments, Steve Hansen caught up with Andy Farrell, New Zealand rugby's recent nemesis, in Tokyo this week.
Swapping stories with opposition coaches may seem unusual but having been around the test rugby block for the best part of 17 years now, Hansen knows virtually every international mentor.
Farrell's defensive systems have caused the All Blacks major problems since the 2017 British and Irish Lions tour but those on-field frustrations don't prevent friendships flourishing.
While he doesn't get on with everyone in the international coaching fraternity, Hansen shared a similar friendship with former Springboks coach Heyneke Meyer.
In a week such as this, if there's anyone that understands the pressures and emotions surrounding the most important test in four years, it's your opposite number.
Ironically, Hansen mentioning his casual meeting with Farrell helps drive home the reality of the All Blacks' World Cup quarter-final with Ireland.
"Come the final whistle one will go right and one will go left. Stage right would be the way to go. We all understand that," Hansen said.
"I caught up with Andy Farrell yesterday and had a bit of a yarn to him. In that conversation that was brought up, that one of us will be going home. That's just the cold hard facts of the World Cup. We've experienced it ourselves in '07 and there's no guarantees we won't experience it again.
"Ireland are in the situation where they haven't gone past the quarter-finals. They know what it's like to go home so they'll be doing their darndest not to, and we'll be the same.
"You hope it becomes a good game of rugby that excites the tournament, it's not affected by cards and at the end of it no one has any excuses and you then have to take your fate on the chin.
"Sport, like life, is not always fair. Sometimes you're going to get the rub of the green and sometimes you're not but the measure of your character is how you deal with either one of those things when the game is over."
The other side of the equation, one Hansen and All Blacks captain Kieran Read are completely blocking from their minds, is the scenario where defeat immediately ends their respective tenures.
The same is true for Irish coach Joe Schmidt. This will, of course, be the case each week they remain in Japan.
"You haven't got room to get gaga emotional," Hansen said. "When the tournament is over that's when you step back and have a reflection on what's next, what's life going to be like but in the meantime it's not even in your mind.
"You put a lot in so there's a lot of emotional energy used but you don't really suffer from the emotional side until it's all over. You get bone tired. Win, lose or draw that happens."
With pride and passion bubbling within, test weeks are emotional at the best of times but there is no denying a World Cup knockout match is an entirely different beast.
For Read and his men on the field, they must walk the fine line between embracing and suppressing emotions. Get too hyped and there is a danger of losing heads and inviting Nigel Owens to add to the flurry of costly cards we've seen at this tournament.
Equally, though, the grand stage should also inspire.
"You've got to embrace what the occasion is going to bring," Read said. "A finals game will certainly bring you a little bit more nerves, a little bit more pressure, which does create a bit of stuff in you physically which is great to have.
"It's important to mix that with a clear mind. I want the guys to be pretty fired up for this game. We need to be in the right space but you can't be over that line. You've got to be in the right area."
Who deals with this dynamic best will exit Tokyo Stadium stage right.