WALES have pledged to be firing on all cylinders when their Six Nations title defence starts in earnest with a colossal clash in Dublin on Saturday.

Warren Gatland's men produced a sluggish performance when getting their campaign up and running with a 23-15 win against Italy at the Millennium Stadium while rampant Ireland crushed Scotland 28-6 at the Aviva Stadium yesterday.

Things didn't go to plan for the reigning champions, who had hoped to fire a warning shot to those that intent to their title rivals, and they can ill afford a repeat.

Next up is a far sterner challenge in Dublin where one side's Grand Slam and Triple Crown hopes will be in tatters come Saturday evening.

Last time Wales played at the Aviva Stadium they edged a classic thanks to a late George North try and a nerveless Leigh Halfpenny penalty.

They went on to claim a Grand Slam in 2012 and will need to recapture that form if they are to be chasing another clean sweep this year.

"It wasn't the best out there against Italy and we're just glad to have got the result," said number eight Toby Faletau.

"It didn't go to plan and there's no doubt that there are plenty of things to work on but getting the win was all important and I'm sure the boys will prepare well for Ireland.

"It is going to be tough and we do need a significant improvement to win out there but I am confident we can do that.

"We had a good win last time in Dublin but that was two years ago and this will be a huge challenge."

Head coach Gatland was angered by the suggestion that Saturday is a grudge match following his summer decision to leave Irish great Brian O'Driscoll out of the Lions' third Test success against Australia.

Indeed, it is a mouthwatering match-up even without that factor.

"It is a massive challenge for us," said the New Zealander, who was in charge of Ireland between 1998 and 2001. "It is going to be a huge game for both teams.

"We have been champions for the last two years, so every team is going to be targeting their game against us and they will get up for it."