Scarlets 17-29 Northampton
Northampton outscored the Scarlets two tries to one as they recorded an impressive 29-17 victory at the Parc y Scarlets.
Alain Rolland, refereeing his first game in Wales since sending off Sam Warburton in the World Cup semi-final, went some way towards repairing his relationship with Scarlets fans in the very early stages of this match.
He sinbinned Tom May in just the second minute for tamely tossing the ball into the face of Gareth Davies after the whistle had blown but the home side managed just a solitary Rhys Priestland penalty during their ten minutes with an extra man.
After Priestland and Stephen Myler exchanged penalties shortly afterwards, Rolland then reversed a penalty in the Scarlets' favour for another dubious after the whistle offence from Calum Clark. Priestland took full advantage to make the score 9-3.
And then, after half an hour of petulance and refereeing controversies, a game finally broke out when Priestland executed a cross-field kick perfectly and it was gathered comfortably by Viliame Iongi, who put the ball down untouched for the first try.
Myler did add another three points for the Saints before the break but the Llanelli outfit were winning the battle of the breakdown and were good value for their 14-6 half-time lead.
Northampton were grateful for the opportunity to regroup and Jim Mallinder's team-talk did the trick as they edged ahead ten minutes into the second half.
Soane Tonga'uiha lunged over the line from short range after good pressure from the forwards and Myler added the conversion and yet another three points.
Priestland did briefly restore the Scarlets' lead shortly afterwards before Myler added a further two penalties from his unerring right boot.
Both teams had chances as the game wore on but, after the Scarlets had spent a long period camped on the Saints' line and severely tested their defence, Ben Foden dealt the crucial blow.
The England full-back intercepted a pass in his own twenty-two and returned it the length of the field to score. Replacement Ryan Lamb added the conversion with the last kick of the match to effectively knock the Welsh side out of this year's competition.