Winning the Grand Slam is one thing, defending it quite another.
Since the Home Nations championship began in 1883, with France joining in 1910 and Italy in 2000, there have been just 42 clean sweeps, starting with Wales' success in 1908.
And on only five occasions have teams gone back-to-back with Slams (Wales in 1908-09, England in 1913-14, 1922-23 and 1991-92 and France in 1997-98).
Defending the Grand Slam with a championship has been achieved just an additional six times, with Ireland in 1949, England in 1958, 1996 and 2017 and Wales in 1979 and 2013 all following the full set with silverware in the following season.
So rare have clean sweeps been in Ireland’s rugby history, Friday night’s clash against France represents just the fourth time Ireland have defended all the marbles.
It ain’t easy.
In fact, on only one occasion has an Irish side backed up the Grand Slam with a championship and you have to go all the way back to 1949 for that.
Ireland famously won the Five Nations Grand Slam in 1948 with captain Karl Mullen and out-half Jack Kyle among the heroes.
Back then, of course, the fact that the Slam, won with a final day victory over Wales in Belfast, included a Triple Crown was a bigger deal.
Similar to this defence, Ireland began the 1949 edition against France and, perhaps ominously, went down 16-9 in Dublin. Sunday Independent reporter Arthur P McWeeney suggested a "pogrom of some description is bound to follow such a disaster", tongue firmly in cheek.
That was followed up by a fine 14-5 victory over England in Lansdowne Road and things got even better on the road.
Ireland beat Scotland 13-3 in Edinburgh and saw off Wales 5-0 in Swansea for a second Triple Crown in two years.
Off on the final weekend of action, Ireland were crowned champions when Scotland, needing to win to draw level on six points, suffered a 19-3 defeat in Twickenham.
Ireland’s famous 2009 Six Nations win, sealed with a late Ronan O’Gara dropgoal against Wales in the Millennium Stadium, bridged a 61-year gap for a Grand Slam.
Declan Kidney’s men started off the 2010 campaign with a routine home win over Italy in Croke Park before coming distinctly second best in Stade de France, going down 33-10, Ireland’s only try coming from David Wallace late on.
A brace from Tommy Bowe, including a try with seven minutes to play, against England kept Irish title hopes alive.
A round-four win over Wales set up a Triple Crown match-up against Scotland for the final day but a late Dan Parks penalty (below) saw Ireland end their time at HQ with a demoralising defeat.
France rounded off the tournament with a 12-10 win over England that secured a Grand Slam for Les Bleus.
The story of Ireland’s 2019 defence attempt is more widely remembered.
After the all-conquering campaign of 2018, where Joe Schmidt’s side won away in France and England, the team came back down to earth with a bang, largely the shape of Manu Tuilagi.
A marauding English outfit landed the first punch of a wretched 2019 for the Irish, winning 32-20 at the Aviva.
Victories against Scotland, Italy and France had Ireland still in with a championship chance on the final day but Wales, who were going for a Grand Slam, dominated proceedings from start to finish at an open-roofed Principality Stadium (below) and ran out 25-7 winners.
Ireland went off to the World Cup with their tails between their legs.
Claiming a Grand Slam on the even years, when Ireland face away trips to France and England, is considered more difficult to achieve and head coach Andy Farrell has already said that being in with a shout of winning the Six Nations come the final weekend is a realistic goal.
Given how Ireland's World Cup campaign finished, it would certainly be a very respectable 'consolation' prize.
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