Given the history of the fixture, it is no surprise that the outcome of this year’s Guinness Six Nations will be decided, one way or the other, by Ireland’s trip to Wales.
A rivalry that dates back centuries, these two sides first played each other in January 1882, when Wales emerged from Lansdowne Road with a now unconventional looking 2-0 win.
This time around, of course, Cardiff and the Principality Stadium play host, with Wales desperate to seal what would be a first Grand Slam since 2012 and Ireland ready to spoil the party with a win.
Scenarios like this certainly aren’t new to the fixture, with Championships decided, legacies cemented, and hearts broken on countless occasions.
Here, we pick out five of the best Wales v Ireland match-ups from yesteryear.
JJ makes history
The Welsh team during the latter part of the 1970s was one of their all-time greatest: four Championships in five years from 1975-79 and as many Triple Crowns helped to enshrine the likes of Gareth Edwards, Ray Gravell and captain Phil Bennett in the pantheon of rugby’s best.
The third of four Championships – a streak that had the year before been interrupted by a French Grand Slam – came in 1978, a feat they set up with victory over Ireland at Lansdowne Road.
But the ramifications didn’t stop there; win and Wales would become the first side in the history of Rugby’s Greatest Championship to claim three Triple Crowns on the bounce.
It was to be a tightly fought contest in Dublin, with scores kept close thanks to the expert kicking of Steve Fenwick and Tony Ward.
But it was JJ Williams who made the difference, as he darted to the line to seal a 20-16 victory for the visitors, setting up a Grand Slam finale as Wales added the cherry on top with victory over France the following week.
ROG’s forgotten strike
Think of Ronan O’Gara and a famous drop goal in Wales and one immediately springs to mind – more on that later – but the man already had form by the time 2009 rolled around.
A crazy game of rugby played out in a bubbling cauldron of Welsh support saw body blows dealt by both sides in what became a slugfest for the ages.
Scores from Stephen Jones, Martyn Williams and Gareth Thomas, with Keith Gleeson grabbing a pair for Ireland, set up a grand-stand finale, made all the more dramatic when Jones slotted a drop-goal from distance to give Wales their first taste of the lead since the first half.
But more was to come, as a 26-year-old O’Gara let loose with his own effort, set up out of nothing and from way downtown, he split the posts just 30 seconds later and keept Ireland’s Grand Slam hopes alive as they squeezed a 25-24 triumph.
Jones ends the wait
Given their dominance back in the 70s, it would’ve taken a brave soul to predict that Wales would be made to wait 25-years for another Grand Slam after their 1978 triumph.
But a barren patch, as the side struggled to deal with the loss of several crucial individuals, left Welsh fans morbidly pessimistic by the time matchday five of the 2005 Championship arrived.
Mike Ruddock’s men had won four from four in swashbuckling style up until that point, brushing aside Scotland, France, Italy and England, but a visit from Ireland awaited them in the final helping of fixtures.
Any nerves, however, were quickly cast off by a first-half blitz that saw Gethin Jenkins’ try help them to a 16-6 lead at the break.
And they created further breathing space when Kevin Morgan crossed to put them 29-6 up, but it wasn’t to be plain sailing in their bid for a return to the top table.
Marcus Horan and Geordan Murphy responded for Ireland, prompting a nervy finish, but Wales had done enough to keep their rivals at bay, and the Principality Stadium erupted as the whistle rung round, their team glorious once again.
O’Gara for the Grand Slam
Arguably one of the most enduring images from Rugby’s Greatest Championship, Ronan O’Gara’s second appearance on this list is the kick that he is well known for.
Heading into the 2009 Championship Ireland had waited 61 years for a Grand Slam, their last coming back in 1948 – the early days of the Five Nations.
But they went to Cardiff in Round Five with just a win required to end that agonising wait, and it proved a cagey affair as tries from Brian O’Driscoll and Tommy Bowe gave them the lead with time running out.
As fans know, however, history has a strange way of repeating itself when it comes to Rugby’s Greatest Championship, and it was poor Stephen Jones who once again thought that his drop goal had handed Wales victory.
Up stepped O’Gara, however, sound-tracked by the immortal words of commentator Ryle Nugent: “Drop at goal; Grand Slam at stake.”
And, with the weight of a nation on his shoulders, the fly-half once again delivered, not only on the kick, but on an historic Championship.
For Jamie Heaslip – on the field watching aghast as O’Gara’s kick sailed over – it was simply a moment of destiny manifested.
“ROG getting the drop goal – you just felt like it was all going your way.
“I never thought we were going to lose, it was all going our way.
“I don’t think it was confident; I don’t think we were cocky, and I didn’t go around saying it. I just had this sense that it was our time; it was our day.”
Glory in defeat
The 2013 and 2015 Championships provided another odd quirk in the Championship as each side claimed a title while in the process losing to the other.
In 2013 it was the turn of Wales, who lifted Rugby’s Greatest Championship for the second time in as many years, but they got their defence started in the worst possible fashion as Ireland ran out 30-22 victors in Cardiff, thanks to 15 points from Johnny Sexton.
A perfect set of scores from their next four fixtures, however, saw them toasting another Championship as they edged out England for glory.
And it was a feat repeated two years later, this time Ireland suffering 23-16 defeat to their rivals before dusting themselves off again to beat Scotland the following week and edge out England for glory.
With England again well in the mix this weekend, a familiar triumvirate are set to duke it out for the honour of seeing the name etched once more on the famous trophy.