Danny Care scored the only try of the match as Harlequins recorded a 25-9 win over Castres in their opening match in the inaugural European Rugby Champions Cup this evening.
Rory Kockott kicked a penalty to open the scoring for the visitors, but Nick Evans added three points for the English side before the break to leave the teams level at half time.
The Harlequins fly-half was involved again early in the second half, kicking three penalties shortly after the restart, although Kockott kept Castres in contention.
The home side opened up a comfortable lead with 15 minutes to play when Care found a gap, diving over to score the first try in the newly-restructured tournament.
Evans added two more penalties before full time to put the win beyond doubt for Harlequins.