Luther Burrell scored on his final Franklin's Gardens appearance as Saints strengthened their claims on a play-off place with a bonus-point 38-10 win against Worcester Warriors.
Burrell started it all over, bursting through the Worcester defence before diving over inside the opening five minutes.
Taqele Naiyaravoro then began to torment the Warriors, who struggled to come up with any answers as they shipped two tries to the sizeable Australian wing.
And flanker Tom Wood bagged the bonus-point try before the break as the home side, who will now definitely finish in the top six and be playing Champions Cup rugby next season, took total control.
Dan Biggar, who enjoyed a 100 per cent day with the boot, continued to add points after the restart, and Reece Marshall scored Saints' fifth try from a dominant lineout drive.
The win means Saints have moved back up to fourth, one point ahead of Harlequins, knowing that any sort of win at Exeter on May 18 will make sure of a top-four finish.
Quins travel to Wasps on the final day, knowing they will need at least two points from their game at the Ricoh Arena to have any chance of leapfrogging Saints.
Chris Boyd's men have been in fine form in recent weeks, and that continued early on against Worcester.
Burrell, who is leaving for rugby league side Warrington Wolves this summer, started with a bang, flying through in trademark fashion and doing superbly to keep his feet before diving over the line for a special score.
Biggar converted and Saints and their departing centre had exactly the start they wanted.
Worcester tried to respond with a penalty from a tricky position, but fly-half Duncan Weir sent the effort wide.
Saints continued to boss the game after that though, dominating at the scrum, where they won a couple of penalties and kicked to the corner to ramp up the pressure.
The ball eventually went wide to Naiyaravoro and he did the rest, barging his way over in the corner.
Biggar converted brilliantly from the left touchline and Saints were 14-0 up after 20 minutes, with the prospect of a bonus-point win looking strong.
Worcester responded with a Weir penalty, but they were under pressure once again almost immediately, with Saints' fast hands forcing Francois Hougaard to kill the ball.
It earned the Warriors scrum-half a yellow card, and Saints soon had their third try as Naiyaravoro came flying in and shoved his way over the line once more.
Biggar converted to make it 21-3, and Saints had more than 57 minutes to find the bonus-point score.
They only needed eight of them though as Naiyaravoro again took Saints within range and Wood eventually finished the move off by showing great power to get over the line.
Biggar again converted in increasingly tricky conditions and Saints were 28-3 up, leaving Worcester, who had been hit by a string of head injuries, hurting.
The Warriors did finally give their travelling fans something to shout about as Ben Te'o picked up from a tidy offload to score.
Weir converted but the deficit was 18 points at the break, with Saints well in control.
Biggar extended the lead with a penalty on 52 minutes after fine work from Tom Collins and Cobus Reinach prompted a high tackle.
Worcester were constantly under pressure and after Weir fluffed a clearance kick, Saints used the lineout to send Marshall over.
Biggar maintained his fine record from the tee with the successful conversion and Saints started to make use of their bench as they cruised towards the win.
Ken Pisi was introduced for his final Gardens appearance and Saints continued to fly forward in search of another try, but it wasn't to come and the job was well and truly done.
Saints: Tuala (Pisi 66); Collins, Hutchinson, Burrell, Naiyaravoro; Biggar (Francis 63), Reinach (Mitchell 61); Waller (c) (van Wyk 68), Marshall (Ma'asi 68), Franks (Hill 68); Coles, Lawes (Onojaife 71); Gibson, Wood, Harrison (Ludlam 61).
Worcester Warriors: Pennell; Humphreys (Heaney 5), Venter (Lance 25), Te’o, Adams; Weir, Hougaard; Waller (Black 63), Annett (Singleton 61), Schonert (Milasinovich 30); Bresler (Fatialofa 54), Barry (Kitchener 54); du Preez, Lewis (Hill 40), van Velze (c).
Referee: Christophe Ridley