Ireland became back-to-back Guinness Six Nations champions by crushing Scotland’s quest for a first Triple Crown in 34 years with a scrappy 17-13 win.

Andy Farrell’s hosts were well below their free-flowing best in Dublin but avoided any major ‘Super Saturday’ drama to retain the championship title.

Andrew Porter’s second-half try fatally broke the resistance of the stubborn Scots to ignite the St Patrick’s weekend celebrations and satisfy an expectant capacity crowd at the Aviva Stadium.

Hooker Dan Sheehan set Ireland on course for glory – and a 10th successive win over Scotland – with an opportunistic first-half score, while Jack Crowley kicked seven points.

A pair of first-half Finn Russell penalties meant Gregor Townsend’s men trailed just 7-6 at the break and he added a late conversion following Huw Jones’ consolation try.

Yet the Scots were powerless to prevent Ireland bouncing back from the disappointment of their dream of successive Grand Slams being agonisingly ended by England last weekend.

Underdogs Scotland crossed the Irish Sea with a slender chance of snatching the title but realistically seeking to secure a first Triple Crown since 1990 following a chastening round-four loss to Italy.

Their mission to rip up the script began in positive fashion thanks to an early Russell penalty before Sheehan was gifted his fifth try of the tournament by George Turner’s overthrown lineout.

The fortunate 13th-minute score, converted by Crowley, did little to settle Irish nerves and the fired-up Scots kept up the pressure with another three points from Russell’s boot.

Farrell’s men were struggling to gain meaningful territory during a cagey opening period punctuated with errors and frequent kicking exchanges amid a subdued atmosphere.

Crowley squandered a long-range penalty to stretch the slender advantage as resolute Scotland remained relatively untroubled, while offering a threat on the counter attack.

Ireland, who had been forced to replace injured full-back Hugo Keenan with Jordan Larmour just before kick-off, trudged down the tunnel leading by only a single point and with major room for improvement.

Scotland head coach Townsend acknowledged pre-match that his side needed to produce “something special” to spoil the Irish party and bounce back from a dismal display in Rome.

Crowley made their uphill task slightly harder with a straightforward penalty before the visitors received a major reprieve when Tadhg Furlong’s apparent touch down was chalked off following a lengthy review as referee Matthew Carley deemed the ball had been dislodged.

Heroic last-ditch defending was the only thing preventing a rampant home side showing renewed purpose from fully taking control of the contest.

Scotland flanker Andy Christie superbly halted the weaving Calvin Nash with the try line in touching distance before rusty Ireland replacement Garry Ringrose inexplicably fumbled.

Ringrose, making his first appearance of the tournament following a shoulder injury, atoned with a lung-busting intercept run which led to Ireland’s crucial second try.

Robbie Henshaw was adjudged to have been held up on the line in the immediate aftermath before Porter subsequently powered over from a tap-and-go penalty following a yellow card for Ewan Ashman.

Supporters responded with a rousing rendition of the Fields of Athenry, fully believing the job was done.

However, home fans were forced to endure a nervy final couple of minutes after replacement fly-half Harry Byrne was sin binned for a head-on-head challenge on Russell and Scotland centre Jones broke clear to touch down.

Ireland duly avoided any further issues to jubilantly celebrate a fifth championship title in 11 years – and sixth overall – to underline their status as the northern hemisphere’s leading nation.