Clermont fly-half Brock James missed four penalties as Toulon ground out a 25-19 win in a repeat of last year's Heineken Cup Final.
Former Australia international Matt Giteau was on target with six penalties from seven attempts, adding the conversion for Maxime Mermoz's first-half try.
Damien Chouly racked up the only five-pointer for the visitors but Clermont were hindered by two yellow cards shown to Gerhard Vosloo and Loic Jacquet.
James failed to converted a penalty attempt in the fifth minute, after tighthead prop Carl Hayman was pinged at the scrum.
A second for James from 42 metres out a couple of minutes later left the game still scoreless until Alexis Palisson was penalised for a deliberate knock-on, James landing a 45-metre outfit to put the visitors into the lead.
Giteau, in at fly-half for Jonny Wilkinson, responded with a penalty for Toulon after Clermont infringed at the scrum and added a second kick on the angle from 50 metres out to put Toulon ahead 6-3 with 20 minutes gone.
Clermont then wrapped up the game's first try thanks to Chouly, finishing off a break made by the centre partnership of Regan King and Benson Stanley, with James converting.
The hosts waited no time in pegging a try back thanks to Mermoz, the French international centre finding the line six minutes later after good work from Palisson.
A second penalty for James brought Clermont level at 13-13, but right on the strike of half-time they were reduced to 14 men as Vosloo was sin-binned for repeated offences at the breakdown. Giteau converted the resulting penalty to give Toulon a 16-13 lead at the break.
James squandered the chance to level the scores with his third and fourth missed kicks of the afternoon after half-time, as Giteau made no mistake with his next attempt to open up a six-point lead.
The number tens exchanged further penalties as Toulon carried a 22-16 lead into the final quarter.
A second yellow card for the visitors was shown to lock Loic Jacquet but Giteau failed to land the resulting attempt at goal, rediscovering his range a few minutes later with his sixth penalty of the match to open up a comfortable nine-point margin.
It left Clermont with too little time to claw back the win, but James did add a further penalty to secure a losing bonus point with time running out. The European champions secured the victory.
Pens: Giteau 6
Pens: James 3
Yellow Card: Vosloo
Toulon: 15 Delon Armitage, 14 Drew Mitchell, 13 Mathieu Bastareaud, 12 Maxime Mermoz, 11 David Smith, 10 Matt Giteau, 9 Sebastian Tillous-Borde, 8 Chris Masoe, 7 Steffon Armitage, 6 Pierrick Gunther, 5 Ali Williams, 4 Bakkies Botha, 3 Carl Hayman, 2 Jean Charles Orioli, 1 Xavier Chiocci.
Replacements: 16 Benjamin Noirot, 17 Emmanuel Felsina, 18 Danie Roussouw, 19 Juan Smith, 20 David Smith, 21 Jonny Wilkinson, 22 Michael Claassens, 23 Martin Castrogiovanni.
Clermont:15 Jean-Marcellin Buttin, 14 Aurelien Rougerie, 13 Benson Stanley, 12 Regan King, 11 Sitiveni Sivivatu, 10 Brock James, 9 Thierry Lacrampe, 8 Damien Chouly, 7 Gerhard Vosloo, 6 Julien Kazubek, 5 Loic Jacquet, 4 Julien Pierre, 3 Clement Ric, 2 Benjamin Kayser, 1 Raphael Chaume.
Replacements: 16 Ti'i Paulo, 17 Vincent Debaty, 18 Nathan Hines, 19 Alexandre Lapandry, 20 Ludovic Radosavljevic, 21 Gavin Hume, 22 Noa Nakaitaci, 23 Davit Zirakashvili
>Referee: Jérôme Garces