La Rochelle held off a stirring Toulouse fightback to storm back to the French Top 14 summit with a 27-21 win on Sunday.
Stephen Brett marked his Clermont debut with a last-minute penalty as they escaped from Bordeaux with a 23-23 draw.
Munster will face Toulouse in the Champions Cup quarter-finals on April 1, with defending champions Saracens hosting Glasgow on April 2.
After a frantic final round of Champions and Challenge Cup fixtures, the 2016/2017 quarter-finals have been announced.
Clermont made it eight wins in eight home games with a bonus-point 30-6 rout of Toulon to regain the lead of the Top 14.
Toulon mauled Bayonne 82-14 at Stade Felix Mayol, while Toulouse slipped to a 21-19 loss at Brive.
A review of Saturday's action in the European Challenge Cup, including Cardiff Blues' crushing victory over rivals Bath.
Zebre hooker Oliviero Fabiani has been banned for nine weeks for biting Connacht lock forward Quinn Roux.
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