A first-half try from Tom Guest and three penalties and a conversion from the boot of the ever-reliable Nick Evans ensured Quins finished with six wins from six and 28 points from a possible 30.

Biarritz led 3-0 through an 11th-minute penalty from Dimitri Yachvili in atrocious conditions in France but Quins were level five minutes later courtesy of Evans' first strike of the night.

The wet weather meant whoever claimed the opening try was always going to be in the box seat and it was Quins who were celebrating on the half hour.

Back rower Guest, who replaced the injured Nick Easter in the Quins line up, powered over from a well-worked lineout to put the visitors in control.

Evans' successful conversion had the English Champions 10-3 to the good and it stayed that way until the end of the half, although there was still drama to come in the closing 10 minutes as both teams had a man yellow carded. Quins prop Joe Marler and Biarritz blindside Wenceslas Lauret were both binned to ensure the first six minutes of the second period featured just 14 men apiece.

Yachvili cut the gap to four points after 45 minutes when Mike Brown was penalised for playing the ball off his feet when attempting to clear up Jean-Pascal Barraque's chip ahead halfway inside his own 22 and Quins' lead was down to one when the scrum-half struck again eight minutes later.

But the visitors stayed calm and composed despite the threat of a first defeat of the campaign and two further penalties from Evans after 56 and 73 minutes saw them finish the job in some style.