The Exeter Chiefs have kept their Heineken Cup qualification hopes alive with a 27-16 win over Aviva Premiership leaders Harlequins on Saturday.
Gareth Steenson booted five penalties for Exeter, with second-half tries from Damian Welch and Luke Arscott securing the victory.
Ugo Monye put Harlequins in front with a try in the first half, but the defending champions were unable to hold on to the advantage.
Eighth-placed Exeter moved within five points of the top six, while Harlequins are in danger of losing top spot to Saracens, who face London Welsh on Sunday.
"There were lots of things that were frustrating about the game," Harlequins director of rugby Conor O'Shea said. "I said to the players afterwards that we have been outworked by Exeter.
"We were playing in the wrong areas, giving penalties away. There were times you thought we were going to kick on but I never felt that we had any of that intensity and energy that you associate with the team."
Meanwhile, Jamie Elliott starred with a hat-trick of tries as Northampton Saints thumped London Irish 40-14.
Elliott touched down in both corners and claimed a cross-field kick from replacement Ryan Lamb to cap a memorable outing for Northampton, who jumped to fourth on the table.
Elsewhere, Leicester Tigers bounced back from losses to Harlequins and Saracens with a 48-10 victory over Sale Sharks.
Ed Slater and Matt Smith scored two tries apiece, while Mathew Tait added one of his own as Leicester ran out comfortable winners.