An injury-time try by Simon Webster gave Edinburgh a stunning victory over former Heineken Cup champions Wasps in a captivating pool game.
Edinburgh 32 (13)
Tries: Paterson, Southwell, Webster
Pens: Paterson (5)
Wasps 31 (20)
Tries: O'Connor, Lewsey, Sackey
Cons: van Gisbergen (2)
Pens: van Gisbergen (4)
The hosts had looked set for defeat when Paul Sackey touched down in the 73rd minute to give Wasps a 28-27 lead.
But replacement Webster linked up with his fellow backs to slide in under the uprights for an unlikely win.
Edinburgh's Chris Paterson kicked 17 points but missed some crucial kicks that would have set up victory earlier.
Van Gisbergen and Paterson managed two penalties early on before Wasps took the initial upper hand.
Despite some poor line-out work and often dire handling throughout, they managed to string a slick move together for their opening try.
A stunning break by Van Gisbergen, which saw him dart and dance past the opposition defence, was cleverly recycled and Jonny O'Connor was on hand to ground it.
That lead lasted barely 15 minutes before Paterson intercepted a woeful Alex King pass, kicked ahead and beat Matt Dawson and Josh Lewsey to the chase.
Lewsey made amends with a try from a rebounding Van Gisbergen penalty that gave Wasps a 20-13 half-time lead, which should have been less but for some wayward goalkicking from Paterson.
Paterson's cause, though, was helped five minutes into the second half following a timely break by Phil Godman.
Godman linked up with Francisco Leonelli for a lovely one-two before flicking the ball out of the back of his hand to the fast-charging Hugo Southwell for the try.
The home side's bid to move ahead was further aided by Peter Bracken's sin-binning and then Paterson regained his kicking composure to edge Edinburgh 24-20 ahead.
But in a topsy-turvy finale, Van Gisbergen tightened the gap with a penalty of his own before Paterson responded almost immediately.
The telling moment of the afternoon looked set to belong to Wasps and Sackey, who ran in after his team-mates winged the ball down their back-line in textbook fashion.
But Edinburgh, despite the sin-binning of Simon Taylor, hit back in style in injury time when Webster linked up with Leonelli for the match-winning try.
Edinburgh captain Chris Paterson:
"The turning point was when we pulled it back to 13-13 (after Paterson's try).
"That gave us enormous self-belief and showed us we were capable of coming back at them.
"This win is right up there with our best as it was against a quality side."
Wasps boss Ian McGeechan:
"We didn't execute the basics skills and we will definitely have to step up our game.
"Because of that, I don't think we can afford one more defeat or we'll be out.
"In the game itself, I thought we had managed to ride out their impetus in the game but they played with the ball in the right parts of the field."
Edinburgh: Southwell; Paterson, Di Rollo, Jorgensen, Leonelli Morey; Godman, Blair; Hewett, Hall, Smith; Kellock, Murray; Mustchin, Taylor, Hogg.
Replacements: Webster for Jorgensen (75), Lawson for Blair (58), Jacobsen for Hewett (72).
Not Used: Kelly, Pringle, Strokosch, Hodge.
Sin Bin: Taylor (78).
Wasps: Van Gisbergen; Sackey, Lewsey, Abbott, Voyce; King, M Dawson; Payne, Ibanez, Bracken; Shaw, Birkett; Hart, O'Connor, Dallaglio.
Replacements: Skivington for Shaw (69), J Dawson for Hart (54).
Not Used: Barratt, Rees, Reddan, Brooks, Staunton.
Sin Bin: Bracken (52).
Ref: C Berdos (France).