Saints were overwhelmed at Sandy Park as Exeter Chiefs stormed to a 36-12 victory.
JJ Hanrahan had given Jim Mallinder's men the lead as he hit the Chiefs with a sucker punch, intercepting to score inside the opening five minutes.
But it was all Exeter after that as they grabbed a couple of first-half tries, from Don Armand and Olly Woodburn, before the Chiefs continued to up the ante in the second period.
Jack Nowell, Sam Hill and Woodburn added further scores and beleaguered Saints could only respond through an Ahsee Tuala try in the final play of the game.
The away side weren't helped by injuries before and during the game as Tom Wood was forced to withdraw before kick-off with a shoulder.
And Courtney Lawes was added to an ever-growing injury list, which also includes George North, Louis Picamoles, Stephen Myler and Calum Clark, as the England lock was forced off with a head injury after just 20 minutes.
Exeter also had their problems, with Henry Slade missing and two players forced off during the first half, but Rob Baxter's side continued with real fire and desire to earn a hugely deserved victory.
Saints had gone into the game three points behind sixth-placed Harlequins, who they meet at Franklin's Gardens next Saturday, and they knew they really needed to take something from the trip to Sandy Park.
Mallinder's men stood tall early on, with Teimana Harrison, in particular, a nuisance at the breakdown, helping to relieve pressure.
And Exeter cracked as Ollie Devoto's pass was intercepted by Hanrahan, who sprinted clear to score before converting his own try to make it 7-0 after five minutes.
Exeter's early frustration grew with the loss of prop Greg Holmes and back row forward Dave Ewers to injury.
And the Chiefs suffered more disappointment as Nowell looked to have finished well in the corner, but the TMO intervened and referee JP Doyle disallowed the try.
Exeter were then deemed to have knocked on while intercepting before dotting down to give Saints another reprieve.
The away side were living dangerously and the dam finally burst as flanker Armand drove over and Gareth Steenson added the conversion to level the scores.
Ken Pisi was soon sin-binned for a deliberate knock-on and Exeter scored almost immediately as wing Woodburn flew down the blindside and dived over in the corner.
Steenson missed the conversion in windy conditions and the score remained 12-7 at the break, with Saints having made a massive 111 tackles to Exeter's 32.
Saints were to endure the worst possible start to the second half as Ian Whitten slipped through some despairing tackle attempts to score.
Steenson missed the kick, but the hill was getting ever steeper for Saints, who did finally manage to put a bit of pressure on but could not break through.
At the other end, Ben Foden was forced to intervene defensively on a couple of occasions as the Saints wing used his experience to stop Exeter.
But it wasn't long before the home side scored again as the game's stand-out player, Nowell, found space and beat the cover to eventually ground the ball.
Steenson missed the conversion as the wind took it wide, but the score was now 22-7 and Saints were staring down the barrel.
It got even worse when Hill glided through to score and Steenson converted to stretch the gap to 22 points with 10 minutes to go.
And the indefatigable Exeter weren't done yet as impressive wing Nowell handed the ball to Woodburn for an easy run to the line.
Replacement fly-half Joe Simmonds converted to put the icing on the Exeter cake before Tuala scored in the corner.
The try wasn't celebrated by Saints and Hanrahan missed the conversion to round off a horrible afternoon for the men in white.
Exeter Chiefs: Turner; Nowell, Whitten, Devoto (Hill 56), Woodburn; Steenson (Simmonds 70), Townsend (Chudley 52); Rimmer (Moon 49), Yeandle (c) (Cowan-Dickie 56), Holmes (Williams 6); Dennis, Parling; Ewers (Salvi 11), Armand, Horstmann.
Saints: Tuala; K Pisi (Estelles 52), Burrell, Mallinder, Foden (Tuitavake 67); Hanrahan, Groom (Dickson 59); A Waller (Ma'afu 57), Hartley (c) (Haywood 59), Brookes (Denman 57); Day (Ratuniyarawa 58), Ribbans; Lawes (Dickinson 20), Gibson, Harrison.
Referee: JP Doyle