Replacement prop ClÃ©ment Ric snatched a late try bonus point for Clermont in their 32-11 victory over the Scarlets.
A brace of second half tries from Naipolioni Nalaga along with efforts from Jamie Cudmore and Ric secured the victory for last year's beaten finalists who extended their undefeated home run to 68 games.
Rhodri Williams touched down late on for the Welsh region but the damage was already done in a blistering 20 minute spell from the hosts midway through the second half.
The win sent the Top 14 leaders above the Scarlets in Pool 4 with 10 points from their opening three matches.
Clermont piled on the pressure from the outset and Simon Easterby's side withstood waves of attacks before Australian fly-half Brock James kicked the hosts into a three point lead after 10 minutes.
Fijian powerhouse Nalaga thought he scored the game's first try soon after but the touchline came to the Scarlets' rescue thanks to strong defending by the returning Liam Williams.
The French giants increased their lead thanks to a second penalty from James after referee JP Doyle carried on the advantage given to the hosts in the build-up to Nalaga's near-miss.
Scarlets continued to throw their bodies on the line in defence and managed a rare trip into Clermont's half that ended with Rhys Priestland, back from international duty, kicking the Welsh side's first points of the match.
Clermont continued to play on the front foot, despite losing Welsh full-back Lee Byrne through injury, but the game continued to be plagued by stoppages as the Scarlets defended resolutely.
The visitors came desperately close to levelling on the stroke of half-time but Priestland saw his long-range strike bounce back off the post as Clermont took a slender lead into the interval.
Clermont eventually found the breakthrough nine minutes into the second half as former Llanelli lock Cudmore scrambled through a huge pile-up to touch down, with the try being awarded after a lengthy delay while the decision was reviewed by the TMO.
James kicked the conversion but the Scarlets hit-back immediately with a penalty from Jordan Williams to cut Clermont's lead to just seven points.
The French giants sniffed blood and with the Scarlets starting to tire Clermont went further ahead as Nalaga gathered James' kick to cross over the whitewash, with the fly-half adding the extras.
Clermont were in full-flow and added a third score as Nalaga scored his second try in quick succession with a well-timed run into the corner to put the home side firmly in control as the game ticked into the final quarter.
Replacement scrum-half Williams scored a consolation try late on for the Scarlets but Clermont sealed the bonus point as substitute prop Ric crossed over to send the Stade Marcel-Michelin crowd into raptures.
Tries: Cudmore, Nalaga 2, Ric
Cons: James 2, Delany
Pens: James 2
Pens: Priestland 2
Clermont: 15 Lee Byrne, 14 Sitiveni Sivivatu, 13 AurÃ©lien Rougerie (c), 12 Regan King, 11 Napolioni Nalaga, 10 Brock James, 9 Thierry Lacrampe, 8 Fritz Lee, 7 Gerhard Vosloo, 6 Julien Bonnaire, 5 Nathan Hines, 4 Jamie Cudmore, 3 Daniel Kotze, 2 Benjamin Kayser, 1 Thomas Domingo
Replacements: 16 Ti'i Paulo, 17 Vincent Debaty, 18 ClÃ©ment Ric, 19 Julien Pierre, 20 Damien Chouly, 21 Ludovic Radoslavjevic , 22 Mike Delany, 23 Noa Nakaitaci
Scarlets: 15 Liam Williams, 14 Frazier Climo, 13 Nick Reynolds, 12 Scott Williams, 11 Jordan Williams, 10 Rhys Priestland, 9 Gareth Davies, 8 Josh Turnbull, 7 John Barclay, 6 Aaron Shingler, 5 George Earle, 4 Jake Ball, 3 Samson Lee, 2 Emyr Phillips, 1 Rob Evans
Replacements: 16 Ken Owens, 17 Shaun Hopkins, 18 Jacobie Adriaanse, 19 Richard Kelly, 20 Johan Snyman, 21 Rhodri Williams, 22 Aled Thomas, 23 Adam Warren,
Referee: JP Doyle (England)
Assistant referees: Martin Fox, Kevin Stewart (both England)