|Harlequins (11) 26|
|Tries: Luamanu, Evans, Visser Cons: Swiel Pens: Evans 3|
|Exeter Chiefs (15) 39|
|Tries: Ewers, Campagnaro, Turner 2, Slade Cons: Slade, Steenson 3 Pens: Slade 2|
Exeter moved level on points with Premiership leaders Wasps after inflicting a costly defeat on play-off hopefuls Harlequins at The Stoop.
At the end of open and free-flowing first half of rugby Exeter led 15-11, with Chiefs tries coming from Dave Ewers and Michele Campagnaro after Matt Luamanu grabbed the opener for Quins.
Nick Evans edged Quins ahead before swapping penalties with Henry Slade.
Two Lachlan Turner tries and one from Slade sealed the bonus-point win.
Tim Visser's try for Harlequins with the final play of the game was of little consequence as the hosts failed to collect a point in defeat, leaving them five points adrift of the play-off places with two games remaining.
Their ambitions can suffer a still greater blow over the weekend as fourth-placed Leicester host Newcastle on Saturday, and Bath - who are level on points with Tigers - travel to Worcester on the same day.
Three second-half tries, including the double from Turner, in an astonishing 11-minute spell ensured a sixth successive bonus-point win for Rob Baxter's side.
Wasps can restore their lead at the summit on Sunday if they beat bottom side Bristol, and the race for a top-two place, and home semi-final, remains tight as third-placed Saracens, defending Premiership and European Cup champions, are still to play over the Easter weekend.
Still, last season's beaten finalists Exeter could do little more to maintain their maiden title aspirations, with Slade contributing 13 vital points in a game watched by England head coach Eddie Jones.
Harlequins director of rugby John Kingston: "Exeter took a complete buffeting for a lot of the game and managed to stay in it, which they should take full credit for, but to come away with nothing is hard to take.
"I said six or eight weeks ago that the play-offs were unlikely to happen in my view and no, that isn't likely to happen.
"My focus has been finishing in the top six so that we can get into the Champions Cup for the first time in three years.
"There's still all to play for and with two games left we have to maximise our opportunities."
Exeter Chiefs boss Rob Baxter: "When you look across a season you can't get emotionally attached to a home semi-final because when that happens you've lost the battle already.
"For us it's about turning up each week and playing well, whether we're at home or away.
"We've been on a good run and why can't that continue?
"Five points here has really helped us with the home semi, but that's not the be-all and end-all.
"We've been to Saracens and won before, albeit not in such a high-profile game. But Saracens would be the same, they'd be comfortable coming to us. It wouldn't be a big issue for them and we shouldn't see it as a big issue for us."
Harlequins: Brown; Yarde, Marchant, Roberts, Visser; Evans, Care (capt); Marler, Buchanan, Sinckler, Matthews, Horwill, Robshaw, Wallace, Luamanu.
Replacements: Gray, Lambert, Collier, Merrick, Ward, Mulchrone, Swiel, Alofa.
Exeter: Turner; Woodburn, Campagnaro, Devoto, Short; Slade, Maunder; Rimmer, Yeandle, G Holmes, Dennis, Parling, Ewers, Armand, Horstmann.
Replacements: Malton, Moon, Francis, Atkins, Salvi, Townsend, Steenson, S Hill.
Referee: Wayne Barnes
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