Damien Penaud's late try capped a powerful second-half display as Clermont dismissed Toulon to set up a Champions Cup semi-final clash with Leinster.
In what was a repeat showdown of the 2013 and 2015 finals - both won by Toulon - the rival French powerhouses were locked at 6-6 at half-time but it was Clermont who finished much the stronger to claim a 29-9 victory at Stade Marcel Michelin.
Clermont winger Noa Nakaitaci crossed for the game's first try in the 60th minute to give his side some breathing space before replacement Penaud wrapped up the victory right at the death.
Scrum-half Morgan Parra contributed 16 points to Clermont's win with Camille Lopez adding a drop goal. All Toulon's points came from the boot of full-back Leigh Halfpenny.
Parra and Halfpenny each sent over two successful kicks during a tight first half which ended all square, but it was the Frenchman who drew first blood after the restart, slotting home his third penalty of the match after number eight Duane Vermeulen had transgressed at a ruck.
Halfpenny squared it up at 9-9 with a 57th-minute penalty, but Clermont powered their way into the driving seat when Nakaitaci went over in the corner.
Parra added the conversion to give his side a seven-point advantage with 19 minutes remaining and leave three-time European champions Toulon with plenty of work to do.
They could not make any dent into Clermont's advantage though, and instead found themselves further adrift when f ly-half Lopez slotted over a drop goal and Parra added a fourth penalty to his tally.
Penaud then cemented the win when he raced clear to touch down for a converted try as Clermont kept alive their hopes of a first Champions Cup title.