Nick Evans blew kisses to the crowd in a triumphant finish to what may be his final home match for Harlequins after nine years with the London club, as the former All Blacks fly-half, who is retiring in the summer, kicked 22 points in a spectacular win over the Premiership leaders.
Wasps had Springbok star Willie le Roux and England lock Joe Launchbury sent to the sin bin in the second half as they let slip a four-point interval lead, and put themselves in danger of blowing a home tie in the Premiership play-off semi-finals next month.
Exeter and Saracens stand ready to overtake Wasps at the top of the table if results this weekend and next go their way, with Sarries possibly able to bump Wasps down to third when the two sides meet in Coventry in the final round of regular league play on 6 May.
Harlequins had seen their dominant form at home dented by losses to Leicester and Exeter in the Premiership here n recent weeks, but this clattering display featuring the dazzling footwork of young gun Joe Marchant and the heavy charges of older hand Jamie Roberts maintained hopes of automatic qualification for next year’s Champions Cup in sixth place.
It may yet depend on next Saturday’s trip to Northampton, who are also in mid-table, with Gloucester and Newcastle in contention, too, with the added complication that if Gloucester finish eighth but win the European Challenge Cup in Edinburgh on 12 May, they will be allocated the English berth in May’s European qualification play-offs involving the PRO12 and Top 14, and which will otherwise go to the seventh-placed club in the Premiership.
Whichever way it may all pan out, Quins have proved they have top quality when they get it right, by beating Saracens here in early season, and now Wasps by a comfortable margin with tries from Tim Visser and Marchant.
Wasps did hardly anything of note with the ball in hand in the first half, but their ever-present pizzazz was clear in a brilliant counter-attacking try with 24 minutes gone.
Evans was tied into a ruck for Quins, leaving Joe Marler at first receiver, and Mike Brown on the next phase kicked long.
Jimmy Gopperth, the other clever Kiwi fly-half on view, spied the chance of a break from halfway, and galloped clear towards the Quins 22.
Dan Robson gave support and despite a lunging tap tackle from Visser, the Wasps scrum-half was able to get over the line, and Gopperth converted for a 7-3 lead.
Evans had booted Quins ahead with a 12th minute penalty, having taken the precaution in case his side do not wind up in the play-offs of waving to the crowd before kick-off and making a farewell speech to them at the end.
Evans added another three points when Karl Dickson’s pass bounced off an offside Wasp.
Dickson was on as a replacement for Quins’ scrum-half Danny Care, who walked off gingerly and applied an ice pack to his right hip, throwing into doubt his participation in next week’s final regular-season league match away to Northampton.
Quins had plenty of territory leading up to the interval, but it appeared they would regret not making anything of an attacking line-out in the Wasps 22, or a long-range penalty attempt by Evans.
Instead Wasps went up the other end and picked off a penalty by Gopperth for an innocuous block on him as he chipped ahead, and it was 10-6 to the league leaders.
Still this is not a happy hunting ground for Wasps, with one win here since 2007, and they fell away against a brilliantly-organised and hungry Quins thereafter.
Kurtley Beale missed an intercept by centimetres as Evans and Chris Robshaw launched a try for Visser down the left, converted by Evans, who also kept chipping penalties while all Wasps could manage was a penalty by Gopperth.
And the Stoop crowd had the conclusion they most wanted as Marchant’s dancing feet took the impressive centre through for a try on 79 minutes, converted by the exultant Evans.
Care said: “Wasps are a very good team , fighting for the league title but it was a very good performance by our boys and you couldn’t have scripted it better for Nick Evans.”
Harlequins: tries: Visser, Marchant; conversions: Evans 2; penalties: Evans 6.
Wasps: try: Robson; conversion: Gopperth; penalties: Gopperth 2.
Harlequins: M Brown; M Yarde, J Marchant, J Roberts, T Visser; N Evans, D Care (capt); J Marler, R Buchanan, K Sinckler, C Matthews, J Horwill (capt), C Robshaw, L Wallace, M Luamanu.
Replacements: J Gray, M Lambert, W Collier, G Merrick, D Ward, K Dickson, T Swiel, A Alofa.
Wasps: W le Roux; C Wade, E Daly, K Beale, J Bassett; J Gopperth, D Robson; M Mullan, T Taylor, P Swainston, J Launchbury (capt), K Myall, J Haskell, T Young, G Thompson.
Replacements: T Cruse, S McIntyre, J Cooper-Woolley, W Rowlands, N Hughes, J Simpson, D Cipriani, A Leiua.
Referee: W Barnes (RFU).