Harlequins (13) 26
Tries: Masson, Guest
Pens: Malone (4)
Cons: Malone (2)
Wasps (15) 25
Tries: Reddan, Waters (2)
Cons: Cipriani (2)
Stand-in captain Chris Malone kicked Harlequins to a tense victory over Wasps in the Guinness Premiership London derby at the Stoop.
Fly-Half Malone converted Tom Guest's 66th-minute try to seal the win after creating Quins' opening score for Tosh Masson in a topsy-turvy tie.
Wasps scored through centre Fraser Waters and scrum-half Eoin Reddan.
But Danny Cipriani missed a late penalty and Dave Walder missed an injury-time drop-goal.
Harlequins boss Dean Richards:
"One-point win, end to end stuff and plenty to shout about. I'm relieved because we gave them opportunities to get back in the match.
"But we created a lot of chances against a Wasps side which is renowned for its defence and had two or three other chances to score.
"We played reasonably well but I don't think anyone was outstanding on the day.
"We didn't finish Wasps off when we had the opportunities and the last 10 minutes were a bit of a dogfight."
Wasps coach Ian McGeechan:
"After 30 minutes I'm wondering how the hell we are still in the game and in the last 30 I thought it was there for the taking for us but we didn't finish.
"Quins started very well and looked sharp and we did well to get some points on the board.
"I felt in the second half we'd got the measure of them and should have been a little bit more ruthless how we finished off.
"But it was a great advertisement for the Premiership."
Harlequins: Mike Brown, David Strettle, Hal Luscombe, Tosh Masson, Ugo Monye, Chris Malone, Danny Care; Ceri Jones, Tani Fuga, John Brooks, Nicolas Spanghero, Jim Evans, Chris Robshaw, Will Skinner, Chris Hala'Ufia.
Replacements: Chris Brooker, Mike Ross, James Percival, Tom Guest, Simon Keogh, Adrian Jarvis, Jordan Turner-Hall.
Wasps: Mark Van Gisbergen, David Doherty, Fraser Waters, Danny Cipriani, Tom Voyce, Riki Flutey, Eoin Reddan; Tim Payne, Joe Ward, Nick Adams, Richard Birkett, George Skivington, John Hart, Rob Webber, James Haskell.
Replacements: Michael Holford, Charlie Beech, Dan Leo, Hugo Ellis, Simon Amor, Dave Walder, Rob Hoadley.