Saints endured a sobering afternoon as Sale Sharks claimed a comprehensive 20-7 Aviva Premiership victory at a windswept AJ Bell Stadium.
Jim Mallinder’s men simply weren’t at the races in a chastening defeat that brought their seven-match winning streak to a shuddering conclusion.
Makeshift second row duo Sam Dickinson and Calum Clark both saw yellow as Sale punished the champions in ruthless fashion.
The hosts were 13-0 up at the break thanks to an Eifion Lewis-Roberts try, which came after Saints had twice held their hosts up, and eight points from the boot of Danny Cipriani.
And Sharks skipper Dan Braid completed the misery of the men in lime with a second-half score.
Replacement Teimana Harrison did manage to ensure Saints would not be nilled as he wriggled over with 16 minutes to go, but Sale were already out of sight.
For Steve Diamond’s men it was a repeat of their heroics on the same ground last March, when Saints were beaten 19-6.
And Mallinder’s side were to suffer a similarly frustrating fate on this occasion as the absence of players such as Courtney Lawes, Christian Day and Samu Manoa cost them dear.
Saints, who went into the game six points clear at the top of the Premiership table, had made a lively start, with Stephen Myler sending a penalty to the corner.
But Sale did their defensive work well, holding out and winning a penalty to relieve the pressure.
From then on, it was to be one-way traffic as the hosts proceeded to turn the screw.
Magnus Lund was stopped just short of the line, but referee Matthew Carley pulled play back for a penalty and Cipriani easily gave his side the lead.
The fly-half was soon doubling the lead after Salesi Ma’afu was penalised at the breakdown and Saints were swaying in the Salford breeze.
In contrast, the Sharks were growing in confidence and squeezing a succession of penalties out of the champions.
Home boss Steve Diamond was so angered by Carley’s refusal to award a penalty try that he headed to the touchline to remonstrate with an official.
Eventually, though, the referee did take some action as Dickinson was sin-binned for tackling a man without the ball.
And Sale finally seized their chance as prop Lewis-Roberts powered over to rub salt in the Saints wounds.
Cipriani converted to put his side 13-0 up with eight minutes to go until half-time and Mallinder’s men were in desperate need of a response.
But there was to be no rapid reply after the interval as Sale continued to boss proceedings, making use of Saints’ failings in the lineout to pile the pressure on.
Myler missed the chance to get his side on the board, failing with a penalty attempt and enduring taunts from the home fans, who sang “are you watching, Lancaster?”.
And it was to get worse for Saints soon after as Calum Clark was sent to the sin bin for killing the ball.
Sale took immediate advantage, with Braid scoring from the resulting lineout drive and Cipriani adding the extras.
When Clark returned to the field, Saints had 16 minutes to get something out of a disappointing afternoon – and Harrison quickly found the score they were seeking.
Myler converted and there was hope that a losing bonus point could be salvaged, but Sale defended stoically to preserve their impressive 13-point margin.
Sale: Haley; Addison, Leota, Tuitupou (Arscott 76), Cueto; Cipriani (Macleod 71), Cusiter (Cliff 76); Lewis-Roberts (de Marchi 76), Jones, Cobilas; Hines, Mills; Braid ©, Lund, Beaumont.
Saints: Foden (Wilson 66); Elliott (K Pisi 66), G Pisi, Burrell, North; Myler, Dickson (Hodgson 71); Corbisiero (A Waller 58), Haywood (Williams 71), Ma’afu (Denman 58); Dickinson, Clark (Onojaife 76); Wood, Nutley (Harrison 58), Dowson.
Referee: Matthew Carley