Wasps' 20-game unbeaten home run in the Premiership came to an end on Sunday as they were beaten 24-21 by Harlequins.
In a tight match, it had looked as though Danny Cipriani would keep Wasps' impressive home form going from the tee, but late penalties from Marcus Smith ensured Quins denied their hosts.
Smith kicked 14 points at the Ricoh Arena to deny Wasps a third win of the campaign, and inflict a first defeat in Coventry since December 2015.
While Marland Yarde and Charlie Walker scored for Harlequins between tries from Christian Wade and Tom Cruse, Smith kicked four penalties - crucially one more than Cipriani.
Despite defeat - losing the last unbeaten record in the league - the bonus point takes Wasps above Saracens into second. The visitors go fifth.