Saints were stung by a second-half fightback as they slipped to a 20-12 defeat at Sandy Park on Sunday afternoon.
Jim Mallinder’s men had led 12-3 at half-time after a brilliant first 40 minutes, which saw Lee Dickson and Ken Pisi score for the men in grey.
But Exeter cranked up the heat in the second period, with relentless pressure paying off in the form of an Olly Woodburn try and a total of 15 points from Gareth Steenson’s boot.
Saints simply couldn’t get out of their own half after the break as they were continually penalised by referee Greg Garner, who sin-binned Mike Haywood in the 49th minute.
And Garner also ruled out a late score with what appeared to be harsh decision against Jamie Gibson.
As it was Saints suffered their third successive defeat at Sandy Park in all competitions and they will now need to rebuild for the Easter Sunday meeting with top-four rivals Harlequins at Franklin’s Gardens.
Mallinder’s men had headed to the west country buoyed by a run of five wins from six Aviva Premiership games.
That had catapulted them into the top four, but they knew they would face a tough test against an Exeter team who had only lost once at home in the league all season.
Saints were given a huge reprieve five minutes in as Ken Pisi was beaten by the bounce of the ball and Ian Whitten latched onto it, but the centre opted to pass to Henry Slade, who dropped the ball with the line beckoning.
But the Exeter pressure was stifling and Saints had to be at their sharpest to stop the home side scoring.
The Chiefs did eventually earn a penalty though, and Steenson landed it with ease from in front of the posts.
Saints mounted a stirring response as some energetic work in the Exeter half ended with Dickson picking up from the breakdown and darting over for his sixth try in as many games.
JJ Hanrahan missed the tough conversion from out wide and he was soon off target with a hugely ambitious penalty from close to halfway.
Exeter were desperate to respond, but their handling was letting them down as they dropped the ball a couple of times under pressure.
Saints’ defence was holding firm and their kicking out of hand was impressive.
They were also dangerous with ball in hand and after Ben Foden led a break, great hands across the field ended with Gibson superbly teeing up Ken Pisi for a score.
Hanrahan finally hit the target with another tricky conversion attempt and Saints continued to turn the screw before the break with only a forward pass denying them another score.
Saints were forced to make a change at half-time with the injured Ahsee Tuala replaced by James Wilson.
Exeter knew they had to make the most of the disruption and they were soon a man up as Haywood was sin-binned for killing the ball.
Saints stood tall at the lineout, stopping the Chiefs from driving them over and winning the scrum.
But it wasn’t long before Exeter got their score as the ball was worked right and winger Woodburn dived over in the corner.
Steenson missed the conversion to leave Saints four points up, but with a man less for a few more minutes and the home crowd lifting the noise, they knew they would be under siege.
Steenson soon added another three points to the tally with an easy penalty and Saints needed to stem the tide.
Slade tried to stick the boot in further, lining up an audacious attempt from close to halfway, but, like Hanrahan in the first half, he wasn’t even close.
Exeter were ramping up the pressure though and Slade had a great chance to send Woodburn over in the corner but the final pass was fluffed.
Saints were penned in, desperate for some respite, but it was one-way traffic and after winning a couple more penalties, Chiefs finally took the three points from the tee.
Saints were 14-12 down with 11 minutes to go and Steenson soon kicked another penalty to make it a five-point deficit with seven remaining.
The game was slipping away from Mallinder’s men, who had failed to trouble the turf in the Exeter 22 during the second period.
And they were to lose their losing bonus point before the end as Steenson’s kick two minutes from time took Exeter eight points clear.
Saints thought they had scored just before the end, but it was ruled out, with Garner harsly penalising them for an illegal challenge in the air.
That compounded a miserable second half and Exeter booted the ball out to spark scenes of celebration among the home supporters.
Exeter Chiefs: Turner; Woodburn, Slade, Whitten, Short; Steenson, Lewis (Chudley 50); Moon (Hepburn 46), Yeandle (c), Williams; Atkins, Parling, Ewers, Armand, Waldrom (Salvi 54).
Saints: Foden; K Pisi, G Pisi, Mallinder, Tuala (Wilson 40); Hanrahan (Myler 55), Dickson (c) (Fotuali’i 65); A Waller (E Waller 66), Haywood, Hill (Denman 69); Craig, Day (Matfield 69); Gibson, Harrison, Fisher (Wood 54).
Referee: Greg Garner