Mark Jones was left to rue missed opportunities and mounting injuries as the Ospreys suffered a heartbreaking 20-18 defeat to Lyon in the EPCR Challenge Cup quarter-final – a result that ended their hopes of a maiden semi-final appearance in the competition.

Despite a spirited display in front of a home crowd at the Swansea.com Stadium, the Ospreys were edged out after Dan Edwards’ late conversion attempt of George McGuigan’s 71st-minute try struck the post, narrowly denying the Welsh region a chance to level and force extra-time.

"It's disappointing because the effort was there, as you would expect, but we definitely dropped below a level of accuracy that we've shown over the last few months," admitted head coach Jones.

"Some of that was down to Lyon, in fairness, and the pressure they put on us around the contact area, but also a lot of skill-set stuff there that we are a little bit disappointed with.

"We couldn't build any back-to-back pressure. They are such a physical team and once you get into that front-door game against them, it becomes quite difficult to out-power them.

"The little errors add up at the end and that's disappointing because a lot of it was in our control."

The defeat was further compounded by a trio of injury blows to key forwards Justin Tipuric, Adam Beard and Rhys Davies – all of whom are likely to miss next weekend’s Judgement Day derby against Cardiff at the Principality Stadium.

"They're being assessed and it is a bit of a mixture," Jones explained. "They're obviously not great or they wouldn't have come off if they were.

"They'll probably miss next week based on what we've seen earlier. But we've not seen any further than that, so I can't say any further than that without speaking to the physios or the doctor."

Tipuric, who was forced off early with a pectoral issue, is particularly in the spotlight as he approaches retirement and is expected to play his final home match for Ospreys against the Dragons on 26 April.

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"He felt something in his pec area that he was uncomfortable with," Jones added.

"When you're a guy in a line-out like he is aerially or uses your hands in the contact area like he does, you've got to be able to use two hands on the rugby field.

"He's a tough cookie so for him to come off, there must have been a serious amount of discomfort for him."

Despite dominating possession and forcing Lyon into over double the number of tackles, the Ospreys lacked composure at key moments and struggled to maintain momentum.

"We wanted the ball, we wanted to dictate the speed of the game, we wanted to move their big guys around," said Jones. "We did move them around, but we just didn't move them around well enough and accurately enough.

"It is a good lesson for us that the closer you get to the finish line the more accurate you have got to be, and all we can do is learn from it and hopefully we get into future knockout games. We want to build on this one and take the next step forward."

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With their European journey now over and the Cardiff-hosted finals no longer in sight, the Ospreys shift their focus back to the United Rugby Championship. 

A top-eight finish – and a place in the play-offs – remains firmly in their sights.

"Judgement Day becomes a big focus for us and we hopefully have an opportunity to have a good crack at that," said Jones.

"If we can get some momentum through the next couple of weeks, hopefully we can push for potentially getting in the top eight when we get to South Africa."

The Ospreys close out the regular season with back-to-back Welsh derbies before travelling to South Africa for a testing final stretch. 

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