Morné Steyn kicked 28 points as Stade Français thumped city rivals Racing-Métro 38-15 to set up a Top 14 semi-final against Toulon.
At Jean Bouin, and on their return to the play-offs, Stade used their dominant scrum and and incisive backs to overwhelm a Racing team that looked short of ideas.
They completely dominated the first half, with a try from Waisea and a penalty try helping them into a 17-0 lead only for Maxime Machenaud to go over on the stroke of half-time.
Racing used the momentum of that try to put up more resistance in the second half, but Stade showed their experience with Steyn keeping the scoreboard ticking over with a succession of penalties, including one from 55 metres out just before the hour.
Jamie Roberts, in his final game for Racing, crossed with 15 minutes remaining, but it was too little too late for the visitors, who say goodbye to the Welshman and Jonathan Sexton after two disappointing seasons.
Stade had won both fixtures between the two teams this season, including an impressive success at Colombes three weeks ago with 14 men, but this was a different context entirely with Racing much the more experienced in knock-out rugby.
That's because Stade hadn't reached the Top 14 play-offs in six seasons, but it looked like they had never been away as they dominated from the off against a Racing side that looked every bit the team that had only scraped into the play-offs.
Stade had the first real chance when Djibril Camara was held up over the line, but they didn't have to wait long to cross for the opening try. After a couple of strong scrums, they turned to their backs and Fijian centre Waisea was put into space by a little stutter step from Sergio Parisse and had enough strength to power over.
Steyn converted and it was Stade who continued to dominate proceedings, with the South African adding a penalty midway through the half to give the home team a deserved 10-0 lead.
Racing had to wait 25 minutes for their opening chance, with Alexandre Dumoulin stepping and going clean through in midfield. He lacked support however and was stopped ten metres out, with Racing then wasting the chance as they coughed the ball up at the next ruck.
A major issue for the visitors was their scrum, under huge pressure throughout the first half, and after one dominant scrum five metres out, Luc Ducalcon paid the price and was sin-binned.
Down to 14 men, Racing had no answer, and Stade logically went back to the scrum, claiming a penalty try as a result. With Steyn's conversion Stade already led 17-0 with five minutes remaining in the half.
Racing looked set for a hammering but they responded just before the break thanks to their in-form scrum-half Machenaud. After turning down a shot at goal to kick to the corner, they set up a rolling maul. While Stade were able to stop them initially, Machenaud peeled off the back and crashed over for his eighth try of the season.
With Sexton's conversion, the deficit was cut to ten at half-time, arguably flattering Racing, who had been comprehensively outplayed.
The second half started like the first, with Stade on the attack, and they were inches away from scoring a third try when Jérémy Sinzelle dived over in the corner, but he lost control of the ball before crossing the line.
They came back for an offside though and Steyn knocked over a penalty from in front to make it 20-7 as Racing returned to a full complement.
That was quickly cancelled out when Hugh Pyle was caught offside, Racing choosing to take the points this time.
Stade marched straight back up the field and when Bernard le Roux was pinged at a ruck, Steyn slotted his third penalty of the evening. Meanwhile in an attempt to change things Racing removed their skipper Dimitri Szarzewski, replaced by Virgile Lacombe.
Steyn continued his perfect night with a long-range three-pointer to stretch the lead to three scores before adding another as Stade led 29-10 with 20 minutes remaining.
Racing were given a sliver of hope when Jonathan Danty was sin-binned for the visitors for taking out Antonie Claassen in the air. However the entrance of Lacombe had coincided with a misfiring Racing lineout and they lost another after kicking for the corner.
They finally found their way through when Roberts powered over from close range, but it made little difference, with Steyn adding three more penalties to complete the rout.
Toulon will start next week's game in Bordeaux as favourites as they look to make it back-to-back titles, but on this form, Stade will provide a considerable obstacle.
Racing, on the other hand, will come back next season with the likes of Dan Carter and Yannick Nyanga and their shiny new stadium, but they look a long way from title contenders and became the first Racing team to lose three successive derbies.
The scorers:
For Stade Français:
Tries: Waisea, Penalty
Cons: Steyn 2
Pens: Steyn 8
Yellow card: Danty
For Racing-Métro:
Tries: Machenaud, Roberts
Con: Sexton
Pen: Sexton
Yellow card: Ducalcon
