Clark crossed on the half hour after a fine break from scrum-half Dave Lewis. Lewis sliced through at a base of a ruck on the edge of the 22 and had the presence of mind to present the ball to be recycled rather than reach for the line when he was dragged down just short.

Gloucester immediately made the most of the extra numbers as Clark dotted down for the only try of the game just moments after Mont de Marsan's Scottish lock Scott Murray had been the first player to be sinbinned.

Clark's try was the only score of the opening half but Tim Taylor made it 8-0 with a 53^rd minute penalty two minutes after replacement hooker Ephraïm Taukafa also saw yellow.

Gloucester flanker Andy Hazell then endured a nightmare spell as he threatened to let Mont de Marsan back into the game. First the veteran openside gave away a penalty that Jean Baptiste Claverie kicked to make it 8-3 and then he threw a flurry of punches and a knee after being taken out late on 55 minutes.

Hazell saw red for his outburst but Gloucester hung on despite having fellow back rower Matt Cox sin binned for his involvement in the same incident.

Billy Twelvetees struck a penalty on 63 minutes to push the visitors two scores clear and an even a second kick from Claverie late on couldn't prevent Gloucester leaving with a valuable win.