Leinster by birth, Munster by team - Johne's aiming to stop Blues' drive for five derby wins
It is the Irish equivalent of Celtic-Rangers and Real Madrid-Barcelona in that there is an all-consuming passion from the supporters and players of Leinster and Munster for what is a sell-out Magners League show at the Aviva Stadium tonight.
Once of Newbridge College and Lansdowne, Johne Murphy followed Geordan Murphy to Leicester Tigers as another one that got away.
The man from the village of Rathangan, in County Kildare, slipped through Leinster's fingers like water. Perhaps, it was just as well. At the time, he was off the radar and a world removed from challenging for inclusion in Leinster's stellar backline.
Murphy emigrated to Leicester to start the serious work of proving to himself and everyone at Leicester he was worth the punt they took on him. At the end of five seasons, he was a regular first-team player and their highest try-scorer for the club in the season 2008-2009.
Now, he is back in the jersey of Munster: "The hype and the build-up is something I have experienced before from the Heineken Cup final between Leicester and Leinster. I am really looking forward to it.
"I am used to the sort of bite from the Leicester-Northampton, Leicester-Wasps matches. Rugby is a massive thing in Ireland now. It is all very soccer orientated in England. I am adjusting to how it is back here with the excitement of everyone over Leinster-Munster.
"It is a shock to the system. I can see from the previous games there is a lot of hurt over the last few years," said Murphy, in reference to the four straight wins for Leinster against their keenest rivals.
Operating in the centre, Murphy, like Luke Fitzgerald, would rather be playing from full-back. But, he is not about to tell Munster coach Tony McGahan and backs coach Jason Holland how to do their jobs.
"I see myself as a back three player. Fifteen is my preferred position, but I am just happy to play wherever Tony and Dutchy (Holland) put me. I will give it a lash."
His first two tries for Munster came against Glasgow Warriors last Friday. They marked him out as a predator with what his teammate Felix Jones described as "a touch of excitement when he gets the ball".
"I was delighted to get off the mark. It was playing on my mind, to be honest. Once you get one, you are up and running. To get two was pretty cool I have to say."
It will take every ounce of his 15-stones frame to make a difference this evening. Every yard will be disputed. Every tackle administered with hurt in mind. There will be fireworks for sure. Let the games begin!
Leinster: R Kearney; S Horgan, B O'Driscoll, G D'Arcy, L Fitzgerald; J Sexton\I Nacewa, I Boss; C Healy, R Strauss, M Ross, N Hines, D Toner, D Ryan, S O'Brien, J Heaslip (capt).
Munster: P Warwick; D Howlett, L Mafi, S Tuitupou, J Murphy; R O'Gara, T O'Leary; W du Preez, D Varley, T Buckley, D O'Callaghan, D Ryan, A Quinlan, N Ronan, D Leamy (capt).