Exeter claimed their first Gallagher Premiership win of the season at the ninth attempt as they outplayed West Country rivals Gloucester 22-15.
The Chiefs have not won in the Premiership since May, but they climbed out of the cellar above Newcastle after a predictably nervy encounter at Sandy Park.
Prop Josh Iosefa-Scott scored a try six minutes from time to secure the points after Gloucester's strong second-half comeback.
Exeter led at the break after touchdowns from scrumhalf Dan Frost and center Tamati Tu, with Henry Slade converting both scores, as Gloucester were reduced to a solitary Santi Carreras penalty.
But tries in quick succession after the interval from fly-half Gareth Anscombe and substitute prop Jamal Ford-Robinson, one converted by Carreras, put them in front.
Carreras, however, also missed the conversion and penalty, and Exeter closed the game with a Slade penalty and an Iosefe-Scott try.
Exeter, 18 points and four places behind Gloucester before kick-off, took the lead in the second minute thanks to a gift from their opponents.
Exeter Chiefs celebrate victory over Gloucester at Sandy Park
Gloucester made a hash of a lineout inside their own 22 through a wayward throw and poor execution, with Frost scrambling for a touchdown and Slade converting.
Slade then converted a long-range penalty before Gloucester opened their account when Carreras comfortably found the target from 35 yards.
But Exeter continued to dominate territory and possession, scoring a second try after 18 minutes when Slade's cross found Tuo to score after Gloucester had been left without defenders.
Slade's conversion put the Chiefs 11 points ahead and they were excellent value after a commanding first quarter that dented their league position.
Exeter Chiefs Jacques Vermeulen is in contention against Gloucester's Ruan Ackermann and Seb Blake
England international Slade offered a threat behind an Exeter pack that showed impressive work rate led by Wales captain and lock Dafydd Jenkins, while Gloucester's vaunted attacking play could not get out of first gear.
The visitors barely managed to get inside Exeter's 22 and could not complain about a 14-3 interval deficit.
Gloucester got an unexpected lifeline within five minutes of the restart as try scorer Tu became the villain when his pass was intercepted by Anscombe, who enjoyed a 45m run to the line unopposed.
Carreras added the extras, and out of nowhere Exeter found themselves under pressure for the first time in the table.
Exeter Chiefs Tamati Tua scores his second try against Gloucester
Gloucester then lost wing Christian Wade, who did not return to action after undergoing a head injury assessment, and there was a quick second blow when Lock Matias Alemanno picked up a hand injury.
But despite the distraction, Gloucester quickly regrouped and scored from close range when Ford-Robinson was put through, although Carreras missed an easy conversion.
And that mistake was punished just three minutes later when Slade kicked a penalty to give Exeter a 17-15 lead early in the final quarter.
Carreras then slotted home a penalty from 25 meters which would have put Gloucester back in front, and the Chiefs could hardly believe such a let-off as the game entered the final 10 minutes.
And Exeter struck from their next attack, with the forwards controlling close to Gloucester's line, and Iosefa-Scott scored a fine finish.