Prop Andrew Porter scored the decisive try after Dan Sheehan had touched down in the first half as Ireland claimed back-to-back Championships for only the third time in their history.

Andy Farrell’s side did not have it all their own way, with the teams separated by just four points for the lion's share of a cagey encounter.

Scotland arrived with their own Triple Crown dreams but misfired in attack and finally ran out of lives in defence as Ireland made their dominance pay after a lot of huffing and puffing.

Hooker Sheehan scored the only try of the first half either side of two penalties from Finn Russell to give Ireland a one-point lead at the break.

The hosts then battered the Scotland line and after being denied on several occasions, finally pushed clear with Porter’s try 15 minutes from time.

Huw Jones scored late to set up a nervy finish but Ireland held on to retain their crown.

CAT AND MOUSE FIRST 40

There was all the fanfare you would expect ahead of a St. Patrick’s weekend showdown in Dublin but Scotland played their role as party-poopers well to begin with.

Andy Christie charged down a James Lowe clearance kick and would have been in for a simple score but the ball just ran away from him and into touch.

Lowe then conceded a penalty for a few too many rolls on the floor and Russell took advantage, splitting the posts for an early Scotland lead.

The visitors then shot themselves in the foot when George Turner overshot a lineout from his own five-metre line, allowing opposite number Sheehan to score the first try of the afternoon, just as he did in Round 5 against England last year.

Russell kicked another penalty shortly after but there was still the feeling that these two were sizing each other up like two heavyweight boxers waiting for their moment to pounce.

Stafford McDowall, making just his second start for Scotland, nearly did just that after evading a Bundee Aki tackle but the centre was chopped down around the 22 by a combination of Jack Crowley and Jordan Larmour.

The game of cat and mouse continued and Scotland blinked first. Christie and Turner got in each other’s way in midfield and allowed Crowley a shot at the posts but he hooked his effort wide left.

The home crowd tried to roar their team into life before the break but it was to no avail, as Ireland’s half time lead remained 7-6.

PORTER MAKES SURE

An error-strewn start to the second half threatened to undo all of Scotland’s hard work. Lowe bounced off two tackles to breach the defence and Zander Fagerson forfeited a penalty which Crowley sent sailing through the posts.

Russell then booted straight out from the restart and the Irish crowd could sense the turning tide.

Centres Aki and Robbie Henshaw made big ground and Ireland thought they had a second try when Tadhg Furlong reached for the whitewash.

But after consulting the TMO and the big screen, referee Matthew Carley identified separation between hand and ball in the grounding process.

With the Scottish scrum under serious pressure it was virtually one-way traffic. Calvin Nash was next to go close but he was thwarted just short of the line by the industrious Christie.

The Scots were defending their own line again after conceding an offside penalty on halfway but after Ireland failed to make them pay as replacement Garry Ringrose knocked on from close range.

Cam Redpath then held Henshaw up but Ireland finally drove over from a five-metre penalty, which also saw Ewan Ashman sin-binned, as Porter muscled to the line.

That looked to be that but late drama was to follow, with replacement Harry Byrne sent to the sin bin before centre Jones weaved through for a seven-point score.

But Scotland's errors had hampered them all afternoon and a knock-on denied them the chance to mount one final attack, handing Ireland the chance to gleefully boot the ball into the crowd and begin the celebrations.