An eight-try display from the double title holders Saracens proved too much for Saints, as the European Champions Cup got underway.
The north-London side started the half well, keeping Saints pressed into their own half, and after a Stephen Myler penalty got Saints off the mark, Liam Williams tip-toed his way through Saints’ defence to get over for the first try of the evening.
Sarries kept the pressure on and scored their second when Brad Barritt crossed the line following a good maul but Saracens.
Williams added a third for Saracens shortly after as he stretched for the line from a tackle and though Farrell missed the conversion Saints were already 19 points behind.
Myler sent a penalty through the sticks after a tussle between Teimana Harrison and Farrell saw the side offered the chance, but then David Ribbans was making his way to the sin bin for bringing down the maul close to the line at the close of the half.
Saracens closed the half with their bonus-point try through former Saints Calum Clark, and instantly added to their score in the second 40, with a Farrell run tearing through Saints’ defence to give Vincent Koch the score.
Saints, much improved in the second half, were disallowed what could have been the try of the game as Tom Collins chipped through for Luther Burrell to chase, the centre knocked on over the line though and Saracens were soon back on the attack.
Wearing Saints down through numerous phases, Saracens eventually sent Mako Vunipola over the line for their sixth try, before adding a seventh moments later through Alex Lozowski.
Saints finally got over the whitewash after 76 minutes of trying, with Francois van Wyk crossing for his first try in a Saints shirt.
The final try of the game came from Saracens, though. The ball rolled out of the Saints ruck over the Saints’ tryline and Ben Spencer dived through to ground the ball and end the game.
SAINTS Tuala; North, Burrell, Francis, Foden; Myler, Reinach; Waller, Hartley (capt), Brookes, Paterson, Ribbans, Lawes, Gibson, Harrison
Subs - Haywood, Van Wyk, Ford-Robinson, Ratuniyarawa, Wood, Groom, Mallinder, Collins
SARACENS Goode; Williams, Bosch, Barritt (capt), Wyles; Farrell, Wrigglesworth; Vunipola, George, Koch, Isiekwe, Kruis, Itoje, Clark, Wray
Subs - Britts, Barrington, Figallo, Day, Burger, Spencer, Lozowski, Taylor
9 mins SAINTS Penalty Myler 3-0
11 mins SARACENS Try Williams Conversion Farrell 3-7
16 mins SARACENS Penalty Farrell 3-10
20 mins SARACENS Try Barritt Conversion Farrell 3-17
29 mins SARACENS Try Williams 3-22
34 mins SAINTS Penalty Myler 6-22
40 mins SAINTS Yellow Card Ribbans
40 mins SARACENS Try Clark Conversion Farrell 6-29
HALF TIME Northampton Saints 6-29 Saracens
43 mins SARACENS Try Koch Conversion Farrell 6-36
65 mins SARACENS Try Vunipola Conversion Farrell 6-43
68 mins SARACENS Try Lozowski Conversion Farrell 6-50
76 mins SAINTS Try van Wyk Conversion Mallinder 13-50
79 mins SARACENS Try Spencer Conversion Farrell 13-57
FULL TIME Northampton Saints 13-57 Saracens