Harlequins' director of rugby Connor O'Shea has praised his team's work ethic following their second victory over Racing Metro inside a week.
Quins followed up their Heineken Cup success over Racing Metro in Nantes last weekend with a gritty 17-3 success over the big-spending Top 14 club on Sunday.
The success revived the Londoners' hopes of progression beyond the group stage, meaning they could become the first ever club to lose their opening two group games and still make the quarter-finals.
Racing paraded four British and Irish Lions in Jamie Roberts, Jonathan Sexton, Mike Phillips and Dan Lydiate and O'Shea questioned the wisdom of paying large salaries.
"Over two weekends we've taken nine points out of a possible 10 against a Racing team with a large squad," the club's director of rugby said.
"We were the better team, with emphasis on team, and that's what made the big difference. Racing had four Lions who started the third Test against Australia out there. Money can help, but it takes time.
"If you're spending in the region of £20million on a squad when we're spending £5million, it's a huge disparity, but that's part of the challenge.
"Sometimes you overpay players. Some people are maybe getting too much money and become comfortable. It's a difficult kettle of fish when you're playing Clermont who have been together for such a long time."
Clermont top Pool Four by four points and must now travel to south west London on the second weekend of January in the pivotal fixture.
Once Quins have faced the Heineken Cup heavyweights, they travel to Scarlets as they seek to complete a remarkable comeback by progressing to the knockout stages.
"Northampton showed against Leinster at the Aviva Stadium what character, physicality and sheer will can do," he continued.
"We have that in abundance as well. Securing a losing bonus point at Clermont in October was bit of a turning point in terms of rediscovering ourselves.
"To have lost our first two games but to be right back in it when Clermont come here is fantastic. We know exactly what we have to do. We've been written off but this team likes challenges."