London Wasps veteran fly-half Andy Goode landed a last-minute drop goal to defeat Exeter Chiefs 19-16 on Sunday at Adams Park.
Dave Lewis' early converted try and Henry Slade's two penalties gave the Chiefs a 13-3 half-time advantage, while Elliot Daly's three-pointer was Wasps' only response before the break.
Successive Goode kicks reduced the deficit to 13-9 before Joe Simpson's touchdown looked to have snatched victory, but Slade levelled matters late on.
However, Wasps' fly-half was the hero when his drop-goal bisected the posts and took them up to sixth in the Premiership.
These teams went into the game level on points in the league table, but it was the visitors that were in command throughout the first period.
It took just one minute for Rob Baxter's men to open the scoring when good work from Jason Shoemark and Dave Ewers set up the position for Lewis to scamper over.
Daly responded for the hosts with a penalty but Slade restored Exeter's seven-point advantage with one of his own.
As the weather deteriorated so did the quality of play and it wasn't until the 31st minute before the Chiefs' fly-half added to the scoreboard with a three-pointer, to take them 13-3 ahead at half-time.
The hosts lifted the intensity after the break and Goode immediately reduced the arrears with his first points from the tee. It wasn't long before the stand-off was once again successful with the boot to take them to within an unconverted try of the visitors.
The comeback was seemingly completed when Simpson crossed the whitewash, but Exeter refused to lie down and Slade equalised with a penalty. However, with time up, Goode took one last shot at goal and secured the win.
Pens: Daly, Goode 2
Drop Goal: Goode
Pens: Slade 3
Wasps: 15 Elliot Daly, 14 Will Helu, 13 Chris Bell (c), 12 Charlie Hayter, 11 Tom Varndell, 10 Andy Goode, 9 Joe Simpson, 8 Rory Pitman, 7 Guy Thompson, 6 Ashley Johnson, 5 Joe Launchbury, 4 Tom Palmer, 3 Jake Cooper-Woolley, 2 Carlo Festuccia, 1 Matt Mullan.
Replacements: 16 Tom Lindsay, 17 Simon McIntyre, 18 Will Taylor, 19 Kearnan Myall, 20 Ed Jackson, 21 Charlie Davies, 22 Joe Carlisle, 23 Andrew Suniula.
Exeter: 15 Luke Arscott, 14 Jack Nowell, 13 Ian Whitten, 12 Jason Shoemark, 11 Tom James, 10 Henry Slade, 9 Dave Lewis, 8 Dave Ewers, 7 Ben White, 6 Tom Johnson, 5 James Hanks, 4 Dean Mumm (c), 3 Hoani Tui, 2 Chris Whitehead, 1 Ben Moon.
Replacements: 16 Jack Yeandle, 17 Carl Rimmer, 18 Alex Brown, 19 Damian Welch, 20 Kai Horstmann, 21 Will Chudley, 22 Gareth Steenson, 23 Sam Hill.
Referee: Andrew Small
Assistant referees: Andy Watson, Stuart Terheege.
Television match official: Graham Hughes