Wasps continued their late-season charge as they edged past Guinness Premiership play-off rivals Sale 29-19 at Adams Park on Tuesday.
It was Wasps' seventh consecutive league victory but the success was overshadowed by a potentially serious knee injury to England captain Phil Vickery after he was twisted awkwardly in a ruck.
If the damage is to his ligaments, as first appeared, then Vickery faces not only missing Wasps' push for the title but also England's summer tour of New Zealand.
Wasps sealed a crucial victory with a try in each half from Tom Voyce and Paul Sackey plus nineteen points from Danny Cipriani's boot.
At 17-3 up Wasps had the game in the bag before Sale full-back Ben Foden set up an exciting finish as he danced over for the Sharks' only try while Charlie Hodgson kicked fourteen points.
Cipriani's trusty left boot edged Wasps clear again and sealed a victory which not only enhances their own play-off chances but puts a dent in Sale's top-four ambitions.
Wasps are past masters at timing their title challenge to perfection, having won a hat-trick of Premiership finals without finishing top of the table.
This season Ian McGeechan's men have had to come from further behind than ever before after winning just one of their first six games but on the final whistle they were sitting pretty in the play-off places.
But there will be serious concerns over Vickery, who was caught in a ruck and went down holding his right knee in obvious agony.
Vickery was strapped up and tried to continue but after two scrums he limped off. He emerged from the changing room midway through the second half on crutches and his knee packed with ice.
It was a sour moment for Wasps in an otherwise dominant first-half performance, marked by Voyce's early intercept try.
Wasps had made an uncertain start, with Josh Lewsey making a couple of early errors as Sale took a 3-0 lead with a penalty from Hodgson.
After being caught holding on, Lewsey then saw an attempted clearance charged down by Luke McAlister inside his own 22. Wasps recovered and although Cipriani missed touch it provided an unlikely platform as Foden threw a looped pass which Voyce picked off to run 50 metres and score.
Sale were committing numbers to the breakdown, counter-rucked hard and enjoyed repeated success in turning over Wasps' possession.
But in wet conditions they could not find a chink in Shaun Edwards' defence and Wasps remained in the ascendancy, bossing possession and territory through to the interval.
McAlister missed a long-range penalty shot for Sale but Cipriani missed two of his own before edging Wasps into a 10-3 lead, while all eyes were on Vickery hobbling from the field.
Wasps had opted for a five-two forwards split on the bench and will have been grateful for it with Joe Worsley and Tim Payne both brought on at half-time.
Wasps pulled 17-3 clear with a sizzling try from Sackey, who began the move with a surging break deep into the Sale half and finished it off down the right after neat play from Cipriani, Voyce and Fraser Waters.
At that point the match seemed dead and buried. Sale had offered very little and the loss of Worsley to the sin-bin did not seem to unduly bother Wasps.
But Foden then took matters into his own hands and made a series of elusive runs from deep before cutting through some unusually slack Wasps tackling to score by the posts.
Then a fourth Hodgson penalty brought Sale back to within four points and set up a grandstand finish - but Wasps closed the game out expertly.
But Lewsey's break left Sale's defence in disarray and they conceded a penalty under their own posts which Cipriani slotted with ease.
Tries: Voyce, Sackey
Cons: Cipriani 2
Pens: Cipriani 5
Pens: Hodgson 4
Yellow card: Worsley (Wasps - 52 mins)
Wasps: 15 Josh Lewsey, 14 Paul Sackey, 13 Fraser Waters, 12 Riki Flutey, 11 Tom Voyce, 10 Danny Cipriani, 9 Eoin Reddan, 8 John Hart, 7 Tom Rees, 6 James Haskell, 5 Richard Birkett, 4 Simon Shaw, 3 Phil Vickery, 2 Raphael Ibanez (c), 1 Tim Payne.
Replacements: 16 Joe Ward, 17 Tom French, 18 George Skivington, 19 Pat Barnard, 20 Mark McMillan, 21 Mark Van Gisbergen, 22 Joe Worsley.
Sale Sharks: 15 Ben Foden, 14 Mark Cueto, 13 Luke McAlister, 12 Lee Thomas, 11 Oriol Ripol, 10 Charlie Hodgson, 9 Sililo Martens, 8 Nathan Bonner Evans, 7 Magnus Lund, 6 Jason White (c), 5 Dean Schofield, 4 Chris Jones, 3 Stuart Turner, 2 Sebastien Bruno, 1 Lionel Faure.
Replacements: 16 Neil Briggs, 17 Eifion Roberts, 18 Brent Cockbain, 19 Sean Cox, 20 Richard Wigglesworth, 21 Elvis Seveali'I, 22 Selorm Kuadey.
Referee: Andrew Small