|European Champions Cup|
|Exeter (14) 33|
|Tries: Horstmann, Waldrom 2, Short 2 Cons: Steenson 3, Hooley|
|Ospreys (7) 17|
|Tries: Dirksen, Penalty try Cons: Biggar 2 Pens: Biggar|
Exeter are in the European Champions Cup quarter-finals after a stunning final round of games in Pool Two.
They richly deserved a bonus-point win over Ospreys, who went to Devon as group leaders with hopes of a first quarter-final since 2010.
But Bordeaux-Begles' shock 37-28 win at Clermont Auvergne helped the Chiefs top the pool on points difference.
Thomas Waldrom and James Short each scored two tries for Exeter with Kai Horstmann also going over.
A rollercoaster of emotions
Exeter trailed Ospreys by five points in the table going into the game, while Clermont Auvergne - beaten finalists in 2013 and 2015 - were two points behind the Welsh team.
With an impressive home record in Europe and two early tries in the bag Clermont - with Exeter in charge in the south west - looked to be going through, but Bordeaux stunned the hosts with four tries.
Even then Clermont could have progressed had they finished within seven points to secure a losing bonus point, but Morgan Parra turned down a penalty in front of the sticks which would have sent them through and ran it instead, and the chance went begging.
It was symptomatic of a frenzied end to an extraordinary final day in Pool Two, with Exeter number eight Waldrom admitting after the final whistle that he had no idea the Chiefs were through.
Even Exeter boss Rob Baxter was not sure if his side had qualified.
"We knew the score was staying pretty close between Clermont and Bordeaux, and it all started getting really confusing. We didn't know if we needed to kick the ball off the pitch at the end or score another try," said Baxter.
"Qualifying out of this pool today was very unlikely. Anyone who laid a bet on it has probably made a fortune.
"It has been an incredible finale to the weekend. It is always nice when hard work gets rewarded, and I think that is what we have seen today."
Horstmann scored for Exeter after only two minutes, before wing Hanno Dirksen powered over in response for the visitors.
But while Ospreys' endeavour never ceased, Exeter controlled the key back-row battle and dominated attacking play out wide.
With 10 minutes remaining Ospreys earned a penalty try that gave them a slim hope.
But number eight Waldrom's second try killed that off and replacement Will Hooley added the final points.
Ospreys' poor run continues
Exeter were criticised in some quarters for fielding a weakened side in round five at Bordeaux-Begles.
Defeat duly followed for the Aviva Premiership's second-placed team in France, but against the Welsh region the Chiefs took the field with an unbeaten home record this season to defend and did so in some style.
Along with a lack of progress in Europe, Ospreys have now not beaten an English team away in 10 attempts.
Exeter: Phil Dollman; Olly Woodburn, Michele Campagnaro, Ian Whitten, James Short; Gareth Steenson, Dave Lewis; Alec Hepburn, Jack Yeandle (C), Alex Brown; Jonny Hill, Geoff Parling; Kai Horstmann, Don Armand, Thomas Waldrom.
Replacements: Elvis Taione, Ben Moon, Harry Williams, Ollie Atkins, Tom Johnson, Haydn Thomas, Will Hooley, Max Bodilly.
Ospreys: Dan Evans; Hanno Dirksen, Jonathan Spratt, Josh Matavesi, Eli Walker; Dan Biggar, Brendon Leonard; Paul James, Scott Baldwin, Dmitri Arhip; Lloyd Ashley, Alun Wyn Jones (C); Sam Underhill , Justin Tipuric, James King.
Replacements: Sam Parry, Nicky Smith, Aaron Jarvis, Rory Thornton, Dan Baker, Tom Habberfield, Sam Davies, Owen Watkin.
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