Llanelli 16-29 Munster: Munster moved to the top of Pool Five with a 29-16 success at Stradey Park, ending Llanelli Scarlets' European dreams in the process.
Skipper Ronan O'Gara kicked 17 points, including converting tries from David Wallace and Marcus Horan, to help his side reign in the rain.
The result was also sweet revenge for their quarter-final defeat to the same opponents last year, while also being their first win at the venue in five years.
Knowing only a win would do to keep their hopes of qualification alive, the Scarlets battled hard - even scoring the opening try through Regan King.
But they were to be undone by their own lack of discipline, O'Gara making them pay with a perfect kicking performance.
The Irish outhalf slotted over two early penalties to put his side into a lead before they found themselves down to 14 men.
Lifiemi Mafi chased back brilliantly to deny Dwayne Peel a try just before the line but was penalised for wrapping up the ball, allowing Rhys Priestland, standing in at 10 for the injured Stephen Jones, to kick the Scarlets' first points and meaning 10 minutes in the sinbin for his offence.
Boosted by the extra man the hosts scored an excellent opening try. Mark Jones capitalised on a poor clearing kick to out-pace three players before handing on to Gavin Evans, who passed out for King to slide in at the corner.
Priestland converted to put the Scarlets in front for the first time, though their lead did not last for long as within eight minutes O'Gara had kicked Munster 12-10 in front.
His second penalty followed the sin-binning of Jones for holding on and, a man light, the Scarlets leaked a crucial try before half time.
Peter Stringer's smart piece of thinking to take a quick line-out deep inside the opposition's 22 allowed David Wallace an easy run-in that also left an easy conversion for O'Gara,
A fifth penalty made it 22-10 at the break, a lead that proved more enough as the second half was ruined by heavy rain that made the pitch a boggy mess.
Priestland gave the Scarlets a glimmer of hope in the gloomy conditions with two penalties in between a break in play for a hailstorm.
However, Deacon Manu was sin-binned for a punch off the ball, ending the Welsh side's hopes of a late comeback.
Munster's pack took over after that, prop Horan finishing off a long phase of possession by driving over close to the line for the killer try.
Fittingly O'Gara added the extras to complete an excellent night for both himself and his team as the Scarlets suffered a third straight defeat in this year's competition, leaving them with nothing but pride to play for.
