Perpignan booked themselves a home Heineken Cup quarter-final this coming April after dominating the Scarlets 37-5 at Stade Aime Giral on Sunday.
The French side needed to match Leicester's performance against Treviso to top the pool, knowing that the English champions were likely to score four tries against the Italians.
So there was pressure on Perpignan - although their performance hardly suggested it as the Scarlets were swept aside almost dismissively.
Perpignan were halfway to their target of four tries inside 10 minutes, added another on the half-hour mark and completed the job seven minutes into the second half.
The 2009 French champions set their stall out early, quickly snuffing out any faint hopes Scarlets had of a bonus-point win that would have taken them through.
David Marty opened up the defence with a fine pass to Nicolas Laharrague and when the ball was shipped wide to Jerome Porical, the full-back chipped over the top and was first to the bouncing ball to score.
Porical missed the conversion and shortly afterwards made a dreadful hash of a penalty attempt, but Scarlets' respite was brief.
Perpignan turned over Scarlets' ball in the Welsh side's 22 and hooker Guilhelm Guirardo hurled out a glorious long pass to Farid Sid racing down the right wing. He was well tackled by Sean Lamont but Henry Tuilagi was on hand to scoop up the loose ball and score.
Porical was having a nightmare with the boot and missed woefully from in front of the posts on 15 minutes, but Stephen Jones and Rhys Priestland also failed with penalty attempts for Scarlets.
Perpignan were better off going for tries and they had their third after half an hour, their fearsomely powerful scrum driving the Scarlets eight back before a burst from Florian Cazenave pulled the defence wide and his inside pass to Sid sent the winger racing round under the posts.
Scarlets turned down two kickable penalties late in the half only to turn the ball over in the Perpignan 22 and the final act was an injury-time penalty from Laharrague to stretch the lead to 22-0.
The visitors responded well immediately after the break as powerful running and good hands set up Jonathan Davies to crash over, although that was merely a prelude to the game's key moment.
On 47 minutes Maxime Mermoz darted through the defence off the back of a ruck and Florian Cazenave was in support to take the pass and race 40 metres for the bonus-point try.
With the issue decided, the final half an hour saw the intensity of both sides drop off, although Perpignan's forwards drove over for a fifth try through Gerrie Britz.
The large crowd contented themselves with celebratory Mexican waves, while looking forward to a quarter-final in Barcelona. On this form, Perpignan's opponents will not be.
Tries: Porical, Tuilagi, Sid, Cazenave, Britz
Pen: Porical 2
Perpignan:15 JÃ©rÃ´me Porical, 14 Farid Sid, 13 David Marty, 12 Maxime Mermoz, 11 Julien Candelon, 10 Nicolas Laharrague, 9 Florian Cazenave, 8 Henry Tuilagi, 7 Bertrand Guiry, 6 Damien Chouly, 5 Guillaume Vilaceca, 4 Olivier Olibeau, 3 Nicolas Mas, 2 Guilhem Guirado, 1 Perry Freshwater.
Replacements: 16 Marius Tincu, 17 Kisi Pulu, 18 Benoit Bourrust, 19 Robins Tchale Watchou, 20 David Mele, 21 Gerrie Britz, 22 Ovidiu Tonita, 23 Joffrey Michel.
Scarlets: 15 Rhys Priestland, 14 Morgan Stoddart, 13 Gareth Maule, 12 Jon Davies, 11 Sean Lamont, 10 Stephen Jones, 9 Tavis Knoyle, 1 Iestyn Thomas, 2 Matthew Rees (capt), 3 Simon Gardiner, 4 Lou Reed, 5 Jonny Fa'amatuaniu, 6 Rob McCusker, 7 Josh Turnbull, 8 David Lyons.
Replacements: 16 Emyr Phillips, 17 Rhodri Jones, 18 Phil John, 19 Damian Welch, 20 Ben Morgan, 21 Martin Roberts, 22 Lee Williams, 23 Richie Pugh.
Referee: Dave Pearson (England)
Assistant referees: David Rose (England), Paul Dix (England)