Munster and Ulster will meet in the last eight of the Heineken Cup, while Edinburgh get to host Toulouse at Murrayfield.
No bonus for Blues as they end up with tough trip to Leinster
Munster and Ulster will meet in the last eight of the Heineken Cup - with the winner certain of home advantage in the semi-finals.
The two Irish teams will go toe-to-toe at Thomond Park after the quarter-final seedings were finally settled at the end of a dramatic Sunday.
Edinburgh could then be next up for Munster or Ulster after the Scottish side advanced to the knockout stages of Europe's premier club competition for the first time in eight years.
The Gunners recorded a superb 34-11 win over London Irish at Murrayfield to finish top of Pool Two ahead of Cardiff, who were unable to secure a bonus-point victory against Racing Metro.
Edinburgh boss Michael Bradley told
Sky Sports: "We were watching it (the Cardiff match) up in the booth after our match had finished.
"There was a minute-and-a-half to go and Cardiff had a couple of chances to score, but luckily for us Racing Metro held out.
"It's a huge step forward for Edinburgh (to top the group)."
Tall order
Edinburgh get a home tie against four-time winners Toulouse as their reward, while the Blues' failure to score a fourth try at home means they now face the tall order of a trip to reigning champions Leinster next.
"I think when you get to the quarter-final stage most teams are on level par I think. There are eight great teams left now," said Cardiff flanker Sam Warburton after the 36-30 triumph over Racing.
"Leinster are probably going to be favourites, simply because they have home advantage, but we take bags of confidence into that game."
The other quarter-final sees Saracens - the only English team left standing after the group stages - host Clermont. The winners of that tie will then be at home to either Leinster or Cardiff in the last four.
In the Amlin Challenge Cup, Biarritz - who narrowly missed out on qualification in the Heineken Cup as one of the best runners-up - will now take on Wasps in the quarter-finals.
Harlequins also drop into the second-tier competition and will travel to Toulon, with the victors facing either Stade Francais or Exeter in the semi-finals. Brive welcome Scarlets in the other game.
The quarter-finals of both competitions will take place on April 6/7/8, with the semi-finals set for the weekend of April 28/29.
The Heineken Cup final takes place at Twickenham on May 19, the day after the Challenge Cup showpiece is held at the near-by Stoop, meaning Harlequins could yet get to lift the trophy on home turf.
Heineken Cup quarter-final line-up:Munster v Ulster
Leinster v Cardiff Blues
Edinburgh v Toulouse
Saracens v Clermont
Semi-final draw:Sarries/Clermont v Leinster/Cardiff Blues
Munster/Ulster v Edinburgh/Toulouse
Amlin Challenge Cup quarter-final line-up:Stade Francais v Exeter
Brive v Scarlets
Toulon v Harlequins
London Wasps v Biarritz
Semi-final draw:Toulon/Harlequins v Stade Francais/Exeter Chiefs
London Wasps/Biarritz v Brive/Scarlets
