Connacht blew a 21-point half-time advantage as they finished their Guinness Pro14 campaign with a 41-36 defeat to Scarlets.
John Porch, Abraham Papali'i, Sean O'Brien, Dominic Robertson-McCoy, and Kieran Marmion crossed for Connacht in the first half, while Conor Fitzgerald and Jack Carty kicked 11 points between them.
Tries from Aaron Shingler, Steffan Hughes (twice), Dane Blacker, Tom Rogers, and Javan Sebastian, along with 11 points from the boot of Dan Jones, secured the Scarlets a bonus point win.
The wins saw Scarlets secure Champions Cup qualification.
It took the Scarlets a mere three minutes to score their opening try of a dry evening in Llanelli.
The hosts created an overlap, with a well-timed looping pass from captain Hughes sending Wales international Shingler over in the far left-hand corner.
Connacht hit back with a period of sustained pressure as their forwards lay siege to the Scarlets line, with powerful number eight Papali'i held up over the line.
The Scarlets were starting to get strained by Connacht's pressure, resulting in hooker Marc Jones being sent to the sin bin for illegally killing the ball at the breakdown.
The visitors' pressure finally told with their full-back Porch crossing the line after the Westerners had worked an overlap to the left after a couple of dominant scrums.
Connacht were soon celebrating their second try.
Ireland international scrum-half Marmion was the architect with a break into the Scarlets 22.
The ball was quickly recycled, with a long pass from Fitzgerald taken by former rugby league star Papali'i who powered his way over the line.
Scarlets full-back Rogers had a try disallowed, with referee Ben Whitehouse sending tighthead prop Pieter Scholtz to the sin bin for leading with the elbow into a tackle.
Connacht scored arguably their try of the season with impressive centre O'Brien making a 50 metres break, before offloading to Porch, who delicately flicked the ball back inside for O'Brien to score.
Steff Evans probed and attracted defenders, with a lovely offload sending Hughes over for the Scarlets' second try.
On. Re. Peat.
— Connacht Rugby (@connachtrugby) March 22, 2021
This was just sensational 🔥
🎥: @TG4TV pic.twitter.com/zzy4afTzqZ
But Connacht hit straight back with the hosts missing too many first up tackles and, after going through the phases, Robertson-McCoy dived over from short-range before Marmion crossed to give them a commanding 33-12 lead at the interval.
The second-half was a complete role reversal to the first with the Scarlets scoring three tries in the space of 18 minutes. Hughes was first to score after a strong break from Johnny Williams, before big lock Sam Lousi sent Blacker over.
Rogers then made amends for his disallowed try as he raced down the touchline to bring Scarlets back within two points.
The Scarlets were now rampant and took the lead through Jones' boot after Connacht pulled down the maul, and they extended their lead even further when replacement prop Sebastian powered over from short range, although Carty secured two losing bonus points with a late penalty.
Elsewhere, Cardiff saw their hopes of finishing in the top three come to an end despite a stirring second-half comeback to secure a bonus-point 34-15 victory over Edinburgh at the Arms Park.
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