Scarlets knew they were going to have to do it the hard way but do it they have with a 46-22 win over Munster to claim the Guinness PRO12 title at the Aviva Stadium in Dublin in front of a record 44,558 supporters.

When Wayne Pivac’s team lost their first three games of the season without even picking up a bonus point a day like this would have seemed out of the question.

But under Pivac they have become a well-oiled machine, as dangerous an attacking threat as ever, with the added steel up front and most importantly, genuine belief.

A week after becoming the first away team to win a Guinness PRO12 semi-final, beating Leinster at the RDS, they returned to Dublin and beat Munster in Ireland for the second time this season.

A blistering attacking display from had Munster on the ropes half an hour in, trailing 29-3 having conceded four tries as Scarlets proved that you don’t have to defend to win knock-out rugby.

Liam Williams, Steff Evans, Gareth Davies and the outstanding Tadhg Beirne all crossed in a sensational show of attacking verve, with the Limerick side incapable of slowing the Scarlets waves.

Munster finally got a try of their own on the stroke of half-time, Tyler Bleyendaal crossing and converting his own score, but Rassie Erasmus’ men trailed 29-10 at the break.

Any chance of an unlikely comeback was put to bed in the first 15 minutes of the second half, Rhys Patchell adding another penalty and pushing the lead to four scores as Munster couldn’t find a way through.

Instead it was DTH van der Merwe, in his final game for the region, who ran in try number five, with a brilliant individual score, shaking off a couple of tackles on his way over.

Munster struck twice late on through Andrew Conway and Keith Earls, but Scarlets had the final say with James Davies’ try with the final play of the game.

While Scarlets were the more threatening early on it was Munster who took the lead thanks to a dominant scrum, Bleyendaal slotted the seventh-minute penalty.

In their first Guinness PRO12, Scarlets could have been overawed by the occasion but they bounced straight back with their first try of the game.

It was a sign of what was to come as Patchell spotted space in behind and played a beautiful kick through with Williams beating Earls for the try.

Patchell’s conversion was just off-target, but he found his radar on 17 minutes when Niall Scannell was penalised for going off his feet at the breakdown.

The 8-3 lead didn’t seem a fair reflection of how dangerous the Scarlets looked, but they quickly extended their lead.

Steff Evans finished off one of the tries of the season on 20 minutes as Scarlets were able to regularly find space out wide. Off a turnover it was the quick hands of Irish second row Beirne that made the difference. He put Jonathan Davies away and he and Evans exchanged passes back and forth to eventually send the latter over.

Patchell converted for a 15-3 lead, and two minutes later they should have been over again, Gareth Davies knocking on after another break down the left.

He didn’t have to wait long for his try though, getting on the shoulder of Scott Williams as he broke through and going under the posts.

Munster were shell-shocked, and it got worse just after the half-hour when Beirne collected the ball five metres out and, from a standing start, twisted out of two tackles and reached over.

Leading 29-3, Scarlets were in dreamland, but Munster finally managed to get their hands on the ball for an extended period, and were rewarded with a fine try from Bleyendaal after a pick from the base by CJ Stander and a quick recycle. His conversion cut the deficit to 19 at the break.

Munster needed to build on that score at the start of the second half but instead it was Scarlets who struck first in the second half, Patchell slotting a penalty from 35 metres out on the left.

Trailing by 22 points Munster had it all to do, but they have shown incredible spirit this season and they weren’t about to go down without a fight. Conway’s ability in the air was giving Munster some joy, but a penalty against Peter O’Mahony for a dangerous clearout saw one good opportunity go begging with the hour-mark approaching.

That seemed to take the wind out of the Munster sails, and it was up to Canada winger Van der Merwe to twist the knife. Taking over kicking duties, Williams extended the advantage to 39-10 before Munster’s two late tries.

And in the end it was James Davies, scooping on a loose ball in midfield, who had the final say with a sixth Scarlets try.