Steve Tandy admitted his disappointment after the Ospreys were knocked out of the European Rugby Challenge Cup by Stade Français.
The Swansea-based region fell four points short as the Parisians came out on top 21-25 at Principality Stadium on Sunday.
Tandy reckoned his team had enough chances to secure victory, but paid the price for their mistakes.
“I think we deserved to win the game, but ultimately we paid for some inaccuracies, not finishing off opportunities, and some ill-discipline in the first-half,” Tandy told the Wales Rugby website.
“We still had enough possession and opportunities to finish the game off.
“There is no hiding place, it is disappointing. One team has not done a lot to win the game, but that’s knock-out rugby.
“This week I don’t think it was an attitude thing, we were pretty inaccurate. We conceded two cheap tries and ultimately that is the game.”
Stade went down to 14-men after Josaia Raisuqe’s 52nd-minute dismissal for a second yellow-card offence.
But two second-half tries from Raphael Lakafia and Julien Arias combined with Zurabi Zhvania’s score before the break proved enough for the French side to book a semi-final clash with Bath.
Wales scrum-half and stand-in Ospreys captain Rhys Webb was left disappointed.
“It was very frustrating. It is very disappointing and one that got away ” Webb said.
“We felt in control of that game, we had a lot of possession, the accuracy and discipline cost us in the end.
“They scored two tries I do not think they should have scored. It was mistakes from us, silly mistakes. We had opportunities to score tries, but we cannot dwell on that now.”