Harlequins recorded a comprehensive 33-17 victory over Wasps at the Stoop on Saturday that leaves the visitors just four points above Newcastle.
Rory Clegg kicked two penalties to Nicky Robinson's one inside the first 20 minutes but the game really exploded into life midway through the first-half as the Quins backs sprang into action.
From a good platform inside the opposition 22, Danny Care and Clegg released Mike Brown out wide on the right and he squeezed the ball onto Ugo Monye to score in the corner.
And the league leaders didn't have to wait long for a second try either as another strong run from Monye put the Wasps defence on the back foot, allowing George Robson the time and space to pick from the base of a ruck and stroll over.
The lightning-fast Christian Wade gave the visitors some hope heading into the break though as he latched onto an inside pass from Robinson before sprinting through a gaping hole in the Quins defence to make it 16-10.
The hosts dominated more and more after the break and they soon converted their superiority into points as a typically bulldozing run from Maurie Fa'asavalu created the space for Care to feed captain Chris Robshaw, who crashed over from short range.
Fellow England international Jordan Turner-Hall got in on the act moments later as well, finishing off a superb flowing move that was started by Clegg and travelled through the hands of Brown and Sam Smith to secure a bonus point.
Down by 20 points, Wasps began to lose their discipline and Clegg knocked over another three points after replacement Billy Vunipola had infringed and been sent to the sin bin to add insult to injury.
The visitors didn't give in though and they produced arguably the try of the game through Ross Filipo, who had the easy task of finishing things off in the left-hand corner after Wade first and then Charlie Davies had moved Wasps from their own 22 to the opposition's in a matter of seconds.
Harlequins never looked in trouble though and they comfortably played out the last quarter of an hour to stay top of the table and confirm their place in the end of season playoffs, whilst Wasps remain deep in the relegation mire.
Tries: Monye, Robson, Robshaw, Turner-Hall
Con: Clegg 2
Pen: Clegg 3
For London Wasps:
Tries: Wade, Filipo
Con: Robinson 2
Harlequins: 15 Mike Brown, 14 Ugo Monye, 13 George Lowe, 12 Jordan Turner-Hall, 11 Sam Smith, 10 Rory Clegg, 9 Danny Care, 8 Nick Easter, 7 Chris Robshaw (c), 6 Maurie Fa'asavalu, 5 George Robson, 4 Olly Kohn, 3 James Johnston, 2 Rob Buchanan, 1 Joe Marler.
Replacements: 16 Aston Croall, 17 Mark Lambert, 18 Will Collier, 19 Tomas Vallejos, 20 Tom Guest, 21 Karl Dickson, 22 Benjamin Urdapilleta, 23 Ross Chisholm.
London Wasps: 15 Richard Haughton, 14 Christian Wade, 13 Elliot Daly, 12 Ryan Davis, 11 Tom Varndell, 10 Nick Robinson, 9 Charlie Davies, 8 Sam Jones, 7 Jonathan Poff, 6 Joe Launchbury, 5 Richard Birkett ( c), 4 James Cannon, 3 Ben Broster, 2 Tom Lindsay, 1 Tim Payne.
Replacements: 16 Vladislav Korshunov, 17 Zac Taulafo, 18 Simon McIntyre, 19 Ross Filipo, 20 Billy Vunipola, 21 Lee Robinson, 22 Chris Mayor, 23 Jack Wallace.
Referee: JP Doyle