The Irish were given a serious jolt, after cruising through their first three matches, by a revitalised England in losing at Twickenham but meet a Scots side equally battered and bruised after they lost to Italy.
Not many people will give the Scots a chance against Andy Farrell's side and ending a run of nine successive defeats at the hands of the Irish.
Ireland are also bidding for their 19th successive home win, while Gregor Townsend's side have not won in Dublin since 2010 when the Irish were still at their temporary home of Croke Park.
AFP Sport picks out three things that could be key on Saturday:
Redemption beckons
Farrell was graceful after the defeat by England, but he will not have spared the players, most of whom under-performed, and geed them up for the consolation prize of the title.
"We've got to dust ourselves down because we have a championship to win next weekend," Farrell said.
"There's not a problem getting the lads back on track for next week. Six Nations (titles) are unbelievably difficult to come by."
The manner in which Farrell succeeded in moving the devastated players on from their Rugby World Cup quarter-final defeat by New Zealand augurs well.
"It'll be a big test but we're mature enough as a team at this stage that we'll be able to get ourselves right and realise that it's very much in our control," said flanker Josh van der Flier, one of the few to shine for the Irish last weekend.
Townsend is under pressure as, touted as potential dark horses for the title, the Italy defeat (31-29) exposed his side's fragility in letting slip big leads - they just got away with it in the 27-26 win over Wales but the Italians seized their moment.
The 50-year-old insists his team have progressed since a second successive World Cup first-round exit under him.
"I believe in this group," he said.
"You can look at results and say: 'We've lost to Italy, this team aren't going to take that next step'. Or you can look at where we've grown since the World Cup.
"I still believe the performances the players are putting in can show we can beat anybody."
Van der Merwe looks to hog the limelight
The Scots do possess the armoury to hurt the Irish, though often it depends on which Finn Russell turns up, the one that waves a wand and his magic works or whose radar is switched off for the day.
There is, though, one dependable force to be reckoned with and that is their South Africa-born wing Duhan van der Merwe.
The 28-year-old needs just one try to equal Stuart Hogg's national record of 27 and his historic trio of Calcutta Cup touchdowns against England illustrated how clinical he is when he scents the tryline.
Townsend hails him as being "humble" but his greatest praise for him is how "he backs himself" when he sees an opportunity.
The Irish have been duly warned.
O'Mahony's unwelcome cards
A captain leads by example but in Peter O'Mahony's case he would rather it had not been in terms of ill-discipline.
His two yellow cards set the tone for an area which the Irish had prided themselves on prior to this year's tournament.
The Irish have four yellow cards in total, they had just three in their previous 29 Tests, and conceded a Six Nations-leading 45 penalties.
Tadhg Beirne, who was sin-binned against Wales, said no matter how well you defend there will come a time when the pressure tells and players put their hands where they should not be.
"When teams are putting you under pressure of course you’re going to be more likely to give away penalties because you’re on the back foot," he said.
"We can't be desperate, which at times we were against England. When you get desperate you make stupid decisions and you can go off on your own and go out of the system and that can have a big knock-on effect."