Wales take on Ireland in Dublin this afternoon in one of the most eagerly awaited contests between the two sides for years.
Over the last decade, the annual meeting between the two teams has seen Wales clinch their first Grand Slam for 27 years at the Millennium Stadium in 2005 and Ireland returning the favour four years later at the same venue.
But all the talk in the build-up to today's test match has been of Warren Gatland's Wales lining up against Ireland centre Brian O'Driscoll, for the first time since the New Zealander controversially overlooked the Irishman for last summer's test series decider between the British and Irish Lions and Australia.
Alun Wyn Jones, who captained Wales last weekend in their 23-15 win over Italy, has rejected the idea that 'Gatland versus O'Driscoll' will add extra spice to the occasion.
But Wales prop Adam Jones is in no doubt that Paul O'Connell, who will return as Ireland captain after a chest infection, will have Ireland "revved up" for today's clash at the Aviva Stadium.
"I am under no illusions how fired up they will be," said Jones.
"They've talked down the O'Driscoll-Gatland thing, but I'm quietly confident 'Paulie' (Ireland captain Paul O'Connell) will have them revved up come 2.30pm on Saturday. We know what to expect.
"Since we've been on tours with them (Irish players), you get to know them. There's no dislike there, but we want to beat them, obviously."
– Adam Jones, Wales prop
For the last couple of years we've been the best two teams among the Celts. The Irish boys are very similar to us, they're good guys.I am sure it will be very physical, come Saturday, but I will look forward to having a pint with them afterwards.
That is what's so good about this sport. You can knock seven bells out of each other, then shake the guy's hand and have a pint with him afterwards. There will be no hard feelings.
Warren Gatland agrees with Jones about the physicality of today's test, for which he has made three changes to the starting line-up.
Defending Six Nations champions Wales head into today's encounter having won two of the last three matches between the two sides. The countries have met on 119 occasions. Wales lead the series 65-48, with six draws.
Wales full-back Leigh Halfpenny will win his 50th cap today, while Wales prop Paul James will also hit that landmark if he makes an appearance off the replacements' bench.
Halfpenny's achievement means that, at 25 years and 48 days, he becomes the youngest Wales international to reach 50 caps, beating the previous record held by Dwayne Peel.
But away from individual landmarks being set, both sides will be aware of how much is at stake and the challenge that lies in front of them.
Ireland will head into today's test in the knowledge that they have yet to open a Six Nations campaign with back-to-back wins since they clinched the Grand Slam on Welsh soil five years ago. A win for O'Connell's men today may well give them the confidence to go on and repeat their 2009 heroics and seal the Grand Slam in Paris on 15 March. But whether they'll emerge victorious in their own back yard after a visit from the reigning champions - who are unbeaten on the road in the Six Nations since they were defeated 28-9 in Paris three years ago - is another matter altogether.
R Kearney (Leinster), A Trimble (Ulster), B O'Driscoll, G D'Arcy, D Kearney (all Leinster), J Sexton (Racing Metro), C Murray (Munster), C Healy (Leinster), R Best (Ulster), M Ross, D Toner (both Leinster), P O'Connell (capt), P O'Mahony (both Munster), C Henry (Ulster), J Heaslip (Leinster).
Replacements: S Cronin, J McGrath, M Moore (all Leinster), D Tuohy (Ulster), T O'Donnell (Munster), I Boss (Leinster), P Jackson (Ulster), F McFadden (Leinster).
L Halfpenny (Cardiff Blues); A Cuthbert (Cardiff Blues), S Williams (Scarlets), J Roberts (Racing Metro), G North (Northampton); R Priestland (Scarlets), M Phillips (Racing Metro); G Jenkins (Cardiff Blues), R Hibbard (Ospreys), A Jones (Ospreys), A Coombs (Newport Gwent Dragons), A-W Jones (Ospreys), D Lydiate (Racing Metro), S Warburton (Cardiff Blues, capt), T Faletau (Newport Gwent Dragons).
Replacements: K Owens (Scarlets), P James (Bath), R Jones (Scarlets), J Ball (Scarlets), J Tipuric (Ospreys), R Webb (Ospreys), J Hook (Perpignan), L Williams (Scarlets).