Leinster's abject failure in Castres on Friday night was compounded this afternoon as Wasps closed the gap on the Pool Two leaders to just three points. Wasps' 19-11 win over Edinburgh may not have been a thing of beauty but it sets up an epic clash against Leinster in January.
Instead of heading to Twickenham with the benefit of a six-point buffer zone, Michael Cheika's side now know that defeat to the 2007 champions could end their involvement in the competition.
Outhalf Dave Walder scored all of Wasps' points with a try and faultless kicking display to set up the pivotal showdown with Leinster.
Edinburgh had snatched a narrow 8-7 half-time lead with a slick try from Hugo Southwell and penalty from Phil Godman but Wasps sealed their third Heineken Cup victory of the campaign on the back of Walder's dead-eye boot.
Walder started at number 10 after Danny Cipriani spent the week fighting off a stomach bug and took just 12 minutes to stamp his mark on the game with the opening try.
Edinburgh centre Nick De Luca slipped at the crucial moment as he attempted to clear and after Wasps had built the pressure, Walder straightened between two forwards and fended off scrum-half Mike Blair to score.
A jinking run from Phil Godman then earned Edinburgh their first attacking platform and although Wasps snatched the turnover and Van Gisbergen cleared, Edinburgh's tails were up.
From a lineout on halfway, Godman spun a perfectly weighted pass which allowed Ben Cairns to hit the gap outside Waldouck and then send Southwell over for the try.
Edinburgh took the lead just before the interval with a penalty from Godman but Walder struck back with two successful shots at goal early in the second half as Wasps began to pull clear.
Waldouck was replaced at the interval by Cipriani, who had not looked in prime health as he patrolled the touchline during the opening half but lined up at inside centre.
Walder added a third after referee George Clancy had played an extensive advantage to Wasps, which prompted furious Edinburgh coach Andy Robinson to march out of the stands and berate the fourth official.
Phil Vickery, Simon Shaw and James Haskell all tried to set Wasps in motion with powerful runs but the game degenerated into the dire kick-tennis that marred last weekend's Murrayfield clash.
Replacement David Blair reduced the arrears for Edinburgh but Walder applied the finishing touch with his fourth penalty of the afternoon.
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