Saints suffered a chastening defeat at Sixways as they had the ignominy of being the first team to be beaten by Worcester in the league this season.
Jim Mallinder's men lost 30-15 against the Warriors, who had failed to win any of their previous seven Premiership matches at the start of the 2017/18 campaign.
The manner of the defeat made things worse for Saints as they again looked vulnerable defensively and at scrum time.
Only scores from Ben Foden and Jamie Gibson, plus five points from Stephen Myler, gave the away side anything to shout about.
And the afternoon was to end on the sourest possible note as Rob Horne was shown a second yellow card for foul play before Bryce Heem was awarded a hat-trick try that earned the bonus point for Worcester.
That meant, last weekend's Anglo-Welsh Cup win against the Dragons aside, it was a continuation of a shocking run for Saints.
They have now lost five of their past six games, conceding a try bonus point in each of those defeats, and they face a tricky trip to Sale Sharks next Saturday.
Saints had headed to Worcester hoping to begin their run of three key league games with a win.
And they did start strongly, playing with real tempo and keeping the Warriors on their toes.
The away side's early dominance was rewarded with a penalty in front of the posts, with Myler landing it to make it 3-0.
Saints continued to look sharp, putting pressure on the home defence, but they were almost caught out by a quick break, with Ken Pisi doing well to cover.
Worcester did draw level soon after as Saints were caught offside and fly-half Jono Lance landed the penalty.
And the Warriors wasted little time in going ahead as wing Heem managed to get free on the right and he raced in to score.
Lance missed the conversion, but Saints were 8-3 down and needing a response against a Worcester side who had contained them well.
But things were to get worse when Australian centre Horne, making his first appearance since September, was yellow carded for a high tackle on full-back Chris Pennell.
Saints were shipping penalty after penalty, costing them field position and allowing Worcester to crank up the heat.
And it wasn't long before they scored again, with a dominant scrum used as the platform and Heem coming onto the ball at pace, proving too strong for the Saints defence.
Lance easily added the extras and Saints were 15-3 down when Horne returned from the sin bin just before half-time.
And the lead was extended just after the interval as Worcester won a penalty at the scrum and Lance landed it.
The afternoon showed no sign of improving and the Warriors stuck the knife in once again as Pisi was beaten down the left and Pennell combined with Josh Adams, who scored.
It was a good move from Worcester, who had confidence coursing through their veins, and though Lance missed the conversion, the game was only going one way.
Saints did manage to respond, finally finding a way through as Mallinder offloaded brilliantly for Foden, who had just come on for Pisi, to score.
Myler hit the left post with the conversion, leaving his side 15 points down with 25 minutes to play.
Worcester responded by winning a scrum penalty, but Lance missed.
And Saints gave themselves a chance of a losing bonus point as flanker Gibson made the most of some forward pressure to score.
Myler converted to cut the gap to eight points with three minutes to go.
But a horrible afternoon for Saints was to get far worse as Heem powered over for his third try.
Horne was shown a second yellow card for a tip tackle in the build-up and Lance rubbed even more salt in the already gaping wounds with the successful conversion.
Worcester Warriors: Pennell; Heem, Willison, Mills (Hammond 57), Adams; Lance, Hougaard; Waller (Bower 17), Singleton (Williams 69), Schonert (Milasinovich 70); O'Callaghan (c) (Phillips 60), Spencer; Faosiliva (Scotland-Williamson 66), Lewis, van Velze.
Saints: Mallinder; Pisi (Foden 52), Horne, Burrell (Francis 15), Collins; Myler, Reinach (Groom 68); Waller (van Wyk 72), Haywood (Marshall 72), Brookes (Ford-Robinson 40); Paterson, Dickinson (c) (Moon 60); Wood, Gibson, Harrison (Eadie 60).
Referee: Andrew Jackson