|Harlequins: (13) 20|
|Tries: Dombrandt, Marchant Cons: Smith 2 Pens: Smith 2|
|Wasps (3) 13|
|Tries: Stuart Cons: Sopoaga Pens: Daly, Sopoaga|
Harlequins hooker Dave Ward could face disciplinary action after appearing to spit at Wasps' Thomas Young in his side's win at Twickenham.
Ward was sin-binned after stamping on Young's ankle early in the game, but referee Craig Maxwell-Keys seemed to miss the spit which was shown on TV.
Quins back row Alex Dombrandt scored the fastest league try of the season after 49 seconds.
Joe Marchant added a second which was enough to overcome Wasps.
Marcus Smith kicked two first-half penalties to help put Quins 13-3 up at the interval, with Elliot Daly kicking the only reply for the visitors.
But Will Stuart's try reduced the arrears in the second half before Marchant latched onto a defence-splitting grubber kick from Danny Care to cross for the match-winning score from five metres out.
Lima Sopoaga's penalty set up a tense finish, but Harlequins' defence held firm despite intense late pressure.
Harlequins end the year in the top four after the victory, while Wasps dropped to seventh after Sale's win at Gloucester.
Ward incident overshadows Big Game 11
A crowd of 82,000 packed into Twickenham for the 11th annual 'Big Game' and Ward started the occasion well as his short lineout and quick exchange of passes with Dombrandt sent the flanker over for the first try.
But Ward turned villain soon after as he first appeared to neck roll Young and then moments later seemed to spit in the direction on Young - who was making his 100th Wasps appearance - before stamping on the forward's ankle, albeit with little force.
Citing officer Buster White has 24 hours to lodge a complaint against Ward, who could face a minimum four-week ban that could climb to 12 weeks if it is deemed high end.
Wasps director of rugby Dai Young told BBC Coventry and Warwickshire that he did not see the spit, but did see the stamp on his son.
"There's no need for that rubbish in this game, and it is rubbish," he said.
"The game's hard enough without that nonsense, what happened after that I don't know.
"Walking over and stamping on somebody's ankle, what is the point of that?
"It could have been a red card, but I don't want to make too much of it, that's for the officials to have a look at."
Harlequins director of rugby Paul Gustard told BBC Radio London:
"I'm pleased with the result, the performance wasn't where we wanted it to be, but the critical thing today is that we got the four points and we cement that position in fourth in a very tightly-congested league.
"There are things for us to work on, we didn't really have much ball in attack and our set piece faltered a little bit in the second half.
"But we showed again resilience and tenacity and got the result that we needed."
Harlequins: Brown; Earle, Marchant, Saili, Murley; Smith, Care; Marler, Ward, Sinckler, Symons, Glynn, Dombrandt, Clifford, Chisholm (capt).
Replacements: Crumpton, Auterac, Collier, Merrick, Bothma, Mulchrone, Lang, Ibitoye.
Wasps: Le Roux; Bassett, Campagnaro, Le Bourgeois, Daly; Sopoaga, Robson; Harris, Cruse, Cooper-Woolley, Rowlands, Myall, Shields (capt), Young, Carr.
Replacements: Harris, Zhvania, Stuart, Matthews, Morris, Hampson, Searle, De Jongh.
Referee: Craig Maxwell-Keys.
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