The Joe and Johnny Show has one more matinee to go
Johnny Sexton is the exception to the rule when it comes to playing for Ireland while playing abroad and when it comes to carrying out Joe Schmidt's detailed game-plan.
He is the man most trusted with 'Joe's playbook,' the creator-in-chief for Ireland and the executioner of France, Italy, Wales and Scotland in this Six Nations.
What is the relationship between coach and out-half like? Are they a mirror of each other?
"Father and son," quipped Richie Murphy, the Ireland assistant coach.
"I actually think they're quite different. I don't know what you want me to say. They're just different people.
"They're both very passionate about the game. They're extremely intelligent guys and very savvy in relation to their rugby brains.
"They work together to find situations they can exploit.
"But, I wouldn't say they're very alike."
Former Leinster out-half Murphy, Ireland's skills and kicking coach, has been working with Schmidt and Sexton for eight years.
He knows both men inside-out, as rugby players, what makes them tick, what makes them great at what they do.
The changeover from Ronan O'Gara to Sexton came gradually, Declan Kidney moving back and forth in a rivalry similar to that of Ollie Campbell and Tony Ward back in the late 1970s-early 1980s. The comparison is unavoidable and, in many ways, unmake-able.
"The game has moved on quite a lot in that period of time with how defences are organised," said Murphy.
"Johnny would definitely have been more of a running threat himself.
"ROG was obviously very tactical, very astute with where the game was played and finding corners and stuff like that.
"Johnny has the ability to do that, but he's also interested in playing with the defence that is in front of him and creating mismatches and finding opportunities for guys to attack people," added Murphy.
From 2009, Sexton has grown, matured, improved with age.
"I think what he has now is, there is very few things that happen in a game that he hasn't seen before.
"His presence within the group is much different to 2009 when he was quite a young player.
"I think they're probably the main things, how he works with others, how he deals with Conor (Murray) and Bundee (Aki) and those outside him, how he organises the forwards.
"Over the past number of years, that's improved massively."
There is the impression that England's Owen Farrell took what he learned from Sexton on the Lions tour to Australia and used it to reach for greatness. It hasn't gone unnoticed.
"His ability to create for others is really good," noted Murphy about Farrell.
"He'll try and get our defenders to make decisions early and then he'll pick the right pass on the back of that.
"He obviously has a strong kicking game, is a beautiful place-kicker.
"He's physical in the middle of the park and he's grown into that role.
"He's definitely one of their main men."
Heck, Murphy could be talking about Sexton because the rival number 10s are more similar than different.