The Ospreys were knocked out of Europe after Kieran Hardy’s last-gasp winning try was ruled out in a 28-24 defeat to Ulster in Belfast.
Mark Jones’ side looked to have sealed their place in the Challenge Cup quarter-finals, only for Hardy’s score to be chalked off for a forward pass.
Ulster had started better, with second-row Cormac Izuchukwu forcing his way over early on.
The Ospreys quickly hit back, with scrum-half Reuben Morgan-Williams finding a gap to sneak over.
The Wales international then turned provider, slipping through another gap before feeding Dan Kasende to score.
A Dan Edwards’ penalty extended the Ospreys’ lead, but the home side would reduce that before half-time after Dave McCann scored.
Jacob Stockdale slipped through Jack Walsh’ tackle attempt after the break to hand the home side the lead.
That lead was extended after Nick Timoney slipped through to score out wide.
To make matters worse, Ospreys captain Jac Morgan was shown a yellow card for a high tackle in the build-up.
That left the Ospreys with a hill to climb.
However, they fought valiantly.
Luke Morgan was denied a try out wide, but illegally so – with Jack Murphy’s high tackle resulting in a penalty try and a yellow card.
That made it a four-point game.
Hardy looked to have won it late on, but his try was pulled back for a forward pass by Owen Watkin.
And that would be the end of the Ospreys’ European hopes.
Ulster: Ethan McIlroy; Werner Kok, James Hume, Stuart McCloskey, Jacob Stockdale; Jake Flannery, Nathan Doak: Angus Bell, Rob Herring, Tom O’Toole; Iain Henderson, Cormac Izuchukwu; David McCann, Nick Timoney, Juamo Augustus.
Replacements: Tom Stewart, Sam Crean, Scott Wilson, Charlie Irvine, Bryn Ward, Conor McKee, Jack Murphy, Zac Ward.
Ospreys: Jack Walsh; Dan Kasende, Owen Watkin, Kieran Williams, Luke Morgan; Dan Edwards, Reuben Morgan-Williams; Gareth Thomas, Sam Parry, Rhys Henry, Rhys Davies, Ryan Smith, Huw Sutton, Jac Morgan (capt), Morgan Morris.
Replacements: Efan Daniel, Steffan Thomas, Tom Botha, James Fender, Harri Deaves, Kieran Hardy, Evardi Boshoff, Iestyn Hopkins.
Referee: Anthony Woodthorpe (England)
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