Clermont Auvergne will face Toulouse in the Top 14 final after an emphatic 33-13 defeat of Lyon in Bordeaux on Sunday.
Les Jaunards kept their double hopes alive a month after lifting the European Challenge Cup in Newcastle.
Liam Gill put Lyon in front with a try 15 minutes in, but Greig Laidlaw was on target with three penalties before Damian Penaud touched down for a try that the Scotland captain converted to make it 16-8 at the break.
Alivereti Raka added a second Clermont try just after Lyon prop Clement Ric had been shown a yellow card, but Deon Fourie finished at the other end.
Fourie's score came following Camille Lopez's departure to the sin bin, giving Lyon hope of pulling off a fightback.
It was not to be, though, as George Moala went over following another Laidlaw penalty and Clermont set up a showdown between the regular season's top two at Stade de France next Saturday.