Wales have a history of Grand Slam deciders against France, and a very positive one at that.
The omens are good, 1976, 1978, 2008 and 2012 saw victories for the men in red in Cardiff against France which gave them a Slam on the final day of the Five and Six Nations tournaments.
Only once before have Wales had to come to Paris on the final day of the championship to earn a clean sweep, and that was 50 years ago in 1971, when one of the greatest ever Welsh teams visited the city of lights, and on that day they came away with the spoils.
It was Wales first Grand Slam for 19 years, and also their first victory in Paris in 14 years.
Two brilliant tries sealed the victory. France had led 5-0 with Barry John suffering a broken nose. France wing Roger Bougarel seemed poised to score near the Welsh try line but JPR Williams intercepted and raced 70 yards before finding Gareth Edwards supporting at a tremendous rate to score.
It was still 5-3 to France in the second-half when Barry John slotted over a penalty. But arguably the greatest half back pairing in the history of the game turned the match, Gareth Edwards sent Barry John John to the blindside after hooker Jeff Young had won the ball against the head in the scrum.
John glided between two defenders and went over untouched to score the winning try and give Wales victory in front of a record Paris crowd of 60,000.
This year it will be very different, the cafes outside Gare du Nord will be deserted, and the RER trains that ferry constant hoards of fans to the outskirts of Saint Denis will be minus their considerable human cargo decked in blue and red spilling out onto the platform at La Pleine station, where the short straight walk to the stadium begins.
But whatever the backdrop a Grand Slam is almost within touching distance for a Welsh side that has already exceeded all hope and expectation.
The men in red have scored 17 tries in 4 matches and are the only unbeaten team left in the tournament.
France Grand Slam hopes are over after a last minute defeat to England, but their championship hopes are well and truly alive, they will be hurting and fired up for the Friday night showdown at Stade de France.
The permutations for the title are not quite Stephen Hawking territory, but complex nonetheless.
The equation is very simple for Wales, secure victory at the Stade de France, and they will complete the clean sweep, everything else would be irrelevant as they would be Grand Slam champions.
A draw would also be enough for Wales to claim the title in Paris as the two points would take their tally to 21, with no other side able to catch them at the top of the table.
Even suffering their first loss of the Championship might not prevent them from securing the title, depending on the margin of defeat.
The loss to England means Les Bleus must come away from next weekend’s contest with at least four more Championship points than Wales to keep their title hopes alive.
Therefore, if France win by seven points or less and fail to get a bonus point, then Wales will still be champions.
Should France beat Wales with a bonus point then they could still be crowned champions but they would have to beat Scotland potentially with a bonus point.
So it’s all to play for on Saturday night in a￼ dark and deserted Saint Denis, France v Wales with a Grand Slam at stake, plus ça change.