Harlequins may have confounded the critics with their Heineken Cup win at Racing Metro on Saturday – but Tom Casson was not in the least bit surprised.

Having lost their opening two games in the tournament, to Scarlets and Clermont Auvergne, Quins' chances of making it out of the group stages were pretty much written off.

But with impressive victories over the like of Stade Francias, Toulouse and Biarritz in recent times, as well as taking a losing bonus point off Clermont, Quins once again stuck it to a French opponent to reignite their hopes of progression.

Casson said: “I'm not too sure why we tend to do well against French sides. We're usually the underdogs, but we don't let that affect us. We just love the atmosphere and experience of playing in games like that.

“Saturday was something special, and if you can get yourself up for playing games like that you shouldn't be playing rugby. My debut for Quins was in a defeat against Bayonne, but my Heineken Cup debut was in that magnificent win in Toulouse.

“Nobody gave us any hope in that game as Toulouse hadn't lost at home for year, but the same kind of spirit carried us through that game as did Saturday's. We know that if we put our play on the park we can beat anybody – or at least have a chance.

“As a whole we felt we had been written off, but we have given ourselves a real chance now, although we still have three very hard games. We will be expecting a backlash in the return game this weekend, but we know what we have to do.”

Casson is now getting back into his stride after returning from a long lay off last month, and believes Quins, who have had their season disrupted by injuries, will be a force to be reckoned with in the second half of the season with a more settled squad.

He added: “It's been frustrating for me and for a lot of players, and we just need to get some continuity going. There will be a few big names coming back into the mix in the new year, so we can only get stronger as a squad.”