In a concerted attempt to reclaim their continental empire, Ireland's three provinces will be joined by their fourth, Connacht, not by squeezing through to claim the last place among the 20 contenders but as champions of the Guinness PRO12.
And, as luck would have it, all four are about to plough headlong into French opposition. A weekend surely unprecedented in the realms of Irish-Gallic conflict on the rugby field kicks off in Dublin with Leinster in pursuit of a title which they won three times in four seasons.
In that context, the sight of familiar opponents ought to reinforce the fond hope in and around the capital that history might be about to repeat itself, assuming, of course, that Europe's former triple champions give it a hefty helping shove between the shoulder blades.
Castres were among their early victims this time seven years ago, a campaign that ended in Leinster completing their ice-breaking European conquest against Leicester in the 2009 final at BT Murrayfield. And it will be staged there again for the first time since then next May.
Given what they have experienced in Dublin, Castres could be forgiven for thinking that Somebody Up There has it in for them. They have been to Leinster three times and lost the lot.
Had they been in a boxing ring fighting for a Lonsdale Belt, Leinster would have won the 2011 French champions outright. Under the Marquis of Queensberry's rules, the last duel between them would have been declared a mis-match and stopped inside the distance.
Instead Castres kept battling away only to find themselves hopelessly outpointed. They conceded 50, made up of seven tries from seven different players (Dave Kearney, Eoin Reddan, Sean Cronin, Marty Moore, Tadhg Furlong, Luke McGrath, Darragh Fanning) and seven goals from Ian Madigan.
The full extent of the damage done to Castres in three trips can be gauged by the fact that they have conceded more than 100 points. Talk about déjà vu.
Now that they have really begun to motor with four wins on the bounce, Leinster will be in no mood to take their foot off the accelerator. The latest victory, over Munster at the Aviva Stadium, took them to within a whisker of topping the Guinness PRO12 as reward for staging the biggest occasion of the domestic season to date, anywhere in Europe.
At 40,527 the crowd added up to the biggest for a single match anywhere, eclipsing Toulon's 38,012 against Montpellier earlier this month and beating anything in the Aviva Premiership.
Connacht, next up after Leinster some two hours later that same afternoon, start at home with the kind of tie which they would have only dreamt of during the bleak years when success often amounted to ensuring someone else finished bottom.
Toulouse have been to Galway before, in December 2014 when a 37-9 amounted to hefty retaliation for Connacht's famous victory at the home of the European emperors six days earlier, one made possible by Kieran Marmion's try and Dan Parks' goalkicking.
This, though, will be very different for the only club to win Europe's premier prize four times. Connacht are Guinness PRO12 champions and last week's stirring home win over Ulster offered striking evidence that they have recovered from those early-season wobbles.
Sunday sees Ulster break new ground in France, in Bordeaux at the Stade Chaban Delmas, a venue named in honour of the only French prime minister whose possessions included an international cap. The trick for Ulster will be to pick up where they left off in France last season.
They are 80 minutes away from a rare hat-trick. They won in Toulouse by two points last December on the strength of three tries (Ruan Pienaar, Andrew Trimble, Luke Marshall), and in Oyonnax by one with three more tries (Rory Scholes, Craig Gilroy, Kyle McCall).
Bordeaux, of course, has long been enshrined in Munster folklore. They beat Toulouse 31-25 under Mick Galwey's captaincy in a monumental semi-final at the Chaban-Delmas on May 6, 2000. Two of the substitutes that day are still going - Donnacha O'Callaghan for Worcester and Peter Stringer for Sale, or he will be once he recovers from injury.
While Ulster aim to make it three wins on the bounce in France, Munster's concern will be to avoid three successive defeats. They plunge straight into the deep end against reigning French champions Racing 92 at the Stade Yves-du-Manoir in Paris.
Munster are used to big occasions all over France, most recently in Marseilles three seasons ago when they went close to putting Toulon out for the count. Their galaxy of superstars from New Zealand, South Africa, Australia, Argentina, England and France won 24-16, not that the score tells the real story.
That Munster created the only try of a tense occasion, touched down by Simon Zebo, made defeat all the harder to take. Not for the first time, Jonny Wilkinson responded to recurring indiscipline by firing a fusillade of goals to settle what he called 'one hell of a game.'
The first match of the first round offers the Warriors the chance of striking an early blow for the Guinness PRO12. Leicester Tigers head north to sample the daunting challenge of Scotstoun on a Friday night.
Scarlets, flying the Welsh flag on their own in the Champions Cup, need to beat Sale in Llanelli on Saturday evening if they are to make their presence felt in a pool that includes Saracens and Toulon.
The toughest task of all over the weekend belongs to the last of the Guinness PRO12's seven qualifers in the Champions Cup, Zebre. They go to Coventry where Dai Young's Wasps swept all before them in the tournament last year, including Leinster and Toulon.
Guinness PRO12 Final 2017 Ticket Information: Fans can save up to 20% on selected tickets, and prices start at just €30 adults and €5 child, and be booked via www.ticketmaster.ie. For further information visit http://www.pro12rugby.com/final