Will Greenwood, Tyrone Howe and Brian O'Driscoll were all impressed by Clermont's win at Leinster.
French giants ensured victory through physical masterclass
Clermont Auvergne underlined their Heineken Cup credentials as they secured a relatively comfortable 28-21 victory at reigning champions Leinster to cement their position at the summit of Pool 5.
The French side arrived in Ireland still seething from the manner in which their campaign faultered close to the line last season, and one man - Wesley Fofana - had a particular point to prove.
The France centre was at his best at the Aviva Stadium - collecting a crash ball from Morgan Parra and driving his way over the try-line for the score that put the visitors out of sight.
Leinster are not champions for nothing and duly fought back at the death with tries of their own - Shane Jennings and Fergus McFadden crossing - but ultimately a bonus point was all they had to show for their afternoon.
Danger
World Cup winner Will Greenwood was suitably taken by Clermont's display but made mention of several other teams who could take flawless records into the knockout stages.
Greenwood told
Sky Sports: "Absolutely, Clermont are a very dangerous beast in this year's tournament but there are other sides in it like Toulon, Harlequins and Ulster who also might be going through unbeaten."
Meanwhile, Tyrone Howe was at a loss as to how to beat Clermont without first fielding players who could cope with colossal opposition.
The former Ireland wing said: "You have to match them physically. That is the biggest challenge. You look at the French teams who do have that strength in depth - they can step up. For the rest of the sides, that's the biggest challenge.
"Until you get parity in your set-piece and parity up front, it's very difficult to do things with your back line."
A disappointed Leinster captain Brian O'Driscoll - ruled out of the game by injury - said: "They (Clermont) controlled things extremely well and the power of their back line was huge. The forwards set the platform for them and their backs continually got over the gain line."
