Harlequins romped to a morale-boosting victory over French champions Pia in the Carnegie Challenge Cup fourth round.

The Londoners went into the match in south-west France on the back of four consecutive defeats but they never looked in danger of making it five against limited opponents.

Prop Louie McCarthy-Scarsbrook led the way with a second-half hat-trick as the engage Super League strugglers cut loose with 11 tries in all.

Quins, who brought back Scott Hill for Karl Temata, made a rampant start at Stade Daniel Ambert and were 10 points ahead within quarter of an hour.

The recalled Hill crossed and minutes later Australian hooker Chad Randall did likewise, with Rob Purdham converting once.

Former Canberra Raiders back Matt Gafa was next to score, Purdham adding the kick, before Paul Sykes clinched his eighth try of the season just before the half hour.

Purdham's third conversion of the half rounded off the scoring for the first period as Quins went in 22-0 ahead.

The rout continued soon after the teams re-emerged as Sykes completed his brace in the 47th minute, with former England rugby union international Henry Paul, recalled to the starting line-up, kicking the extra points.

A Lee Hopkins try and Paul kick prompted a mini-revival from the French side with Anthony Carrere and winger Stephano Muniesa touching down.

But McCarthy-Scarsbrook then embarked on his personal burst, Gafa scored again and Andy Smith completed the rout.

Paul ended the match with seven successful kicks from seven.