Reddan's second-half brace set up Wasps' victory
Wasps (6) 27
Try: Cipriani, Reddan (2)
Pens: Walder (2)
Cons: Walder, van Gisbergen (2)
Saracens (13) 26
Try: Castaignede, Johnston, Penney
Pens: Jackson (3)
Two late tries by Eoin Reddan helped Wasps snatch victory after Saracens had looked to be strolling to a win.
With 10 minutes left Wasps were 26-13 down but Reddan repeated last week's brace against Leinster, and replacement Mark van Gisbergen converted both.
Thomas Castaignede's first-half injury time try followed by Cencus Johnston's after the break put Saracens on top.
Although Danny Cipriani pulled one back, Rod Penney's try looked to have sealed the win before the late revival.
Wasps captain Lawrence Dallaglio on Eoin Reddan:
"He's got to be putting a lot of pressure on Peter Stringer and co for the Irish squad.
"I don't think he will score a better try than the one that won the game - he dummied the whole crowd as well.
"It was fantastic, edge of the seat stuff and it keeps the dream alive. Our will to win was outstanding."
Saracens director of rugby Alan Gaffney on losing to their play-off rivals:
"Winning wouldn't have sealed our place but it would have put us eight points clear of Wasps and we'd have been pretty happy.
"We can be harsh on ourselves but tomorrow we have to come in with chins up and move on.
"It's soul destroying. We played some good rugby and had control of the game but we lost control by making errors."
Wasps: Cipriani; Lewsey, Waters, Waldouck, Voyce; King, Reddan; Vickery, Ibanez, Bracken; Shaw, Palmer; Haskell, Rees, Dallaglio (capt).
Replacements: Ward, Adams, Birkett, Hart, McMillan, Erinle, Van Gisbergen.
Saracens: Castaignede; Scarbrough, Penney, Farrell, Ratuvou; Jackson, De Kock; Lloyd, Byrne, Johnston; Fullarton, Raiwalui (c); Vyvyan, Seymour, Skirving.
Replacements: Cairns, Yates, Ryder, Gustard, Rauluni, Powell, De Vedia.