The Guinness Premiership outfit join London Irish, Northampton, Newcastle and Worcester in recording convincing victories on the opening weekend.

Only Bristol's heavy loss in Montpellier on Friday night prevented an English clean sweep.

Saracens ran in seven tries against Mont de Marsan and Eddie Jones' men were never in trouble after a lightning start to Pool Six.

England Under-20 star wing Noah Cato was over the tryline within the opening 60 seconds, and the hosts had secured the bonus point inside 45 minutes.

Scrum-half Neil de Kock was the next player on to the scoresheet before a penalty try and Chris Wyles added to the visitors' woes as they went into the half-time break 25-3 down.

Second-half tries by Andy Saull and Ben Skirving and a second penalty try extended Saracens' lead while 16 points from the boot of Glen Jackson rounded off a comfortable afternoon.

In Pool Four, Overmach Parma caused a surprise and fought off a strong second-half fightback from Brive to win 34-29 while Bourgoin recorded a 21-10 away triumph at Bucuresti in Pool Three.