Bristol were pushed a step closer to relegation from the Aviva Premiership as they fell to a 38-34 defeat against Exeter at Sandy Park.
This latest defeat leaves them eight points behind 11th-placed Worcester with only three games remaining, so Bristol's relegation may be confirmed if they lose at home to Wasps next Sunday.
However, it was still a hugely spirited performance from Bristol against an error-ridden Exeter - and it was rough justice on the visitors that they came away with only two points.
The visitors led 34-31 with only four minutes remaining before a late try from Thomas Waldrom snatched victory away from them.
Waldrom scored two tries for Exeter and there was one apiece for Olly Woodburn, Geoff Parling and Ian Whitten.
Henry Slade converted all four and added a penalty, with Gareth Steenson adding a conversion. Gavin Henson scored 19 points for Bristol with a try, four conversions and two penalties.
Jason Woodward, Will Hurrell and Mitch Eadie also scored tries. Bristol fell behind after only a minute. A chip ahead from Woodward surrendered possession and the Chiefs counter-attacked in style to set up a try for Woodburn.
Slade converted but moments later he gifted Bristol their opening try when his telegraphed pass was picked off by Hurrell, who raced 45 metres to score.
Henson converted and kicked a penalty to put Bristol in front but the visitors suffered an injury blow when flanker Jack Lam was helped off and replaced by Nick Fenton-Wells. However they overcame this setback to stun the hosts with a second try.
This time a stray pass from prop Harry Williams was seized upon by Woodward, who outpaced Jack Nowell on a 75-metre run to the line. Henson again converted.
A careless error from Billy Searle, who knocked on an aimless up and under, gave Exeter a platform in their opponents' 22 and when Bristol were penalised at the resulting scrum, Slade kicked a penalty to leave the hosts trailing 17-10 at the end of the first quarter.
Bristol increased the pressure on the home side with a third try when a strong run from Jack Tovey and a neat pass from Gaston Cortes sent Henson over -- and he added the extras.
The visitors suffered a further blow when Ryan Bevington limped off before Chiefs' lock Mitch Lees became another injury victim.
Parling was Exeter's replacement and with the last movement of the half he scored a crucial try by forcing his way over in the corner.
Slade converted and the home side were back in contention at the interval. Within 33 seconds of the restart, Exeter were level when Whitten crossed for their third try -- but the visitors had the advantage of a keen wind in the second half.
However poor kicking and the concession of frequent penalties prevented Bristol benefiting as the home pack began to take control.
After 52 minutes, Chiefs regained the lead when Waldrom finished off a line-out drive but a Henson penalty and the bonus point try from Eadie - converted by the former Wales international -- gave the visitors a 34-31 lead going into the final quarter.
Exeter brought on Steenson and Michele Campagnaro in an attempt to revive their fortunes. Henson was well short with a long distance penalty attempt and Bristol just could not hang on as Waldrom forced his way over for the winning try.