Llanelli Scarlets became the first Welsh winners of the Celtic League after beating title rivals Ulster in their top of the table clash at Stradey Park.
The Scarlets were crowned champions after overpowering Ulster in front of a sell-out crowd and scupper the Irish province's hopes of a league and cup double.
Stephen Jones gave his team the perfect goodbye present before joining Montferrand by kicking 18 points in a near faultless display and created the Llanelli's crucial try that swung the game - and the title - in their favour.
After edging his side 12-9 ahead with his third penalty five minutes into the second half, Jones pierced the gap behind the on-rushing defence before off-loading for Matthew Watkins to scorch over in the corner on 50 minutes.
Until then there had been precious little to separate the sides, both at near full-strength despite the late withdrawals of Tyrone Howe and Dwayne Peel, with Jones and David Humphreys exchanging kicks in a tight first half.
David Humphreys gave the visitors an early lead with a fourth-minute penalty that was cancelled out ten minutes later by Jones as the opposing outside-halves embarked on a fascinating kicking duel during a tight first half.
But Llanelli stepped up a gear - or two - after the break
and Ulster had little response. Jones added two more penalties before being afforded a standing ovation when he left the field two minutes before time.
Replacement forward Neil McMillan crashed over from a lineout almost immediately afterwards to earn Ulster the bonus point that secured their second place in the league ahead of the Dragons and gave departing coach Alan Solomons at least some consolation before he departs for Northampton.
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Ebbw Vale captain Damien Hudd picked up the biggest accolade of the night at the 11th Principality Premiership Awards Evening held at Principality Stadium, after leading his side to the title for the first time.
Wales assistant coach Robin McBryde is predicting a tough battle against England on Sunday despite the fact they may not be considered to be at full strength. Players will be out to impress Eddie Jones which makes England a dangerous proposition, he says.
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