Six successive home defeats as Saints are edged out by Exeter
The defeat to a largely second-string Chiefs side means Saints have now suffered six successive home defeats and have won just two of their past 10 Gallagher Premiership matches.
Tom O'Flaherty, a regular tormentor of Saints, was the match-winner as he found a way over in the corner with 10 minutes to go.
Saints had roared back from going 14-0 down early on, taking a 19-14 lead in the second half after David Ribbans grabbed a double either side of a superb Henry Taylor score.
But Gareth Steenson's penalty cut the gap to two, and Saints produced an error-strewn finale that has become a theme for much of 2020 as O'Flaherty scored to win it for Exeter.
Saints couldn't get any momentum late on as they sought to respond, and Exeter easily saw the game out as their fine form continued.
It was such a shame for Saints, who had responded so well to their early setbacks.
The dazzling O'Flaherty had tied the hosts in knots before Steenson found Sean Lonsdale, with the flanker charging over the line to score.
Steenson added the extras and he was doing so again soon after as Jannes Kirsten cruised in to make it a flanker double for the Chiefs.
Saints were in real trouble at 14-0 down inside just 12 minutes and they then spent the next 10 minutes knocking loudly on the Exeter door.
But there was simply not way through or over the white wall, with the away side defending their own line with real determination.
Saints just kept coming, time after time, and finally they forced the away side to buckle.
Ribbans was the man who got the job done under the posts, and Biggar added the extras to cut the gap to seven points.
Saints lost Ahsee Tuala to injury, bringing Taqele Naiyaravoro into the game, and they then produced a big defensive set to stop Exeter in their tracks.
It brought the ball back into black, green and gold arms, and they made the most of it in style as a scything break resulted in James Fish finding scrum-half Taylor for a fine score.
Biggar missed the conversion but his side were just two points down at the break after a stirring fightback.
Saints made a sensational start to the second half as some brilliant work from Rory Hutchinson and Biggar carried Saints into the Exeter 22 and Ribbans did the rest with a determined finish.
Biggar added the conversion and Saints led for the first time at 19-14 up.
Saints then lost another wing to injury as Tom Collins was forced off, meaning Piers Francis was introduced.
But Saints were playing with real confidence, defending on halfway and using the ball with real pace when they won it and only a lost lineoit in the Exeter stopped them applying even more pressure.
And after O'Flaherty caused more mayhem down the Exeter right, the away side won a penalty, which Steenson easily landed.
It was a fast and frantic encounter full of blood and thunder as Saints desperately sought the bonus-point score they knew could give them the breathing space they craved.
But it was Exeter who scored next as the ever-impressive O'Flaherty found a way over in the corner after Saints had shot themselves in the foot by conceding a penalty close to halfway.
Steenson missed the conversion but it wasn't to matter as Saints huffed and puffed before Don Armand was awarded a penalty that allowed Exeter to see it out and win the game.
Saints: Furbank; Tuala (Naiyaravoro 36), Proctor, Hutchinson, Collins (Francis 45); Biggar, Taylor (Mitchell 61); van Wyk (Auterac 63), Fish (Matavesi 63), Franks (Hill 57); Ribbans, Ratuniyarawa (Isiekwe 58); Lawes, Tonks (Adendorff 60), Harrison (c).
Exeter Chiefs: Hodge (H Skinner 44); O'Flaherty, Dollman, Hendrickson, Baldwin (Wyatt 71); Steenson, Hidalgo-Clyne (Snow 65); Hepburn (Keast 61), Yeandle (c) (Innard 61), Francis (Petch 61); Dennis (Price 46), S Skinner; Kirsten, Lonsdale, Armand.
Referee: Luke Pearce