The Parkhead side must now negotiate two qualifying rounds to enter the lucrative group stages of the Champions League.

But O’Neill insists the thrilling run, which included defeats of Blackburn, Celta Vigo, Stuttgart and Liverpool, has put Celtic back among the big players in European competition.

He said: “The efforts have reawakened Celtic and have invoked a great interest in the club.

“In terms of Europe, we have been dormant for so long and it was satisfying to make Celtic a positive name in European football once again.

“The machine is cranking up again and hopefully we can go on to build on this experience.

“We have two qualifying games to get into the Champions League and that will be our immediate concern when we start back at pre-season training.”

But O’Neill maintains he and the players will still need time to digest the events of a season which saw them miss out on the UEFA Cup and a third successive Bank of Scotland Premier League title at the last hurdle.

He told celticfc.net: “I need to go away and reflect on it.

“It is obviously still hurting and the disappointment will hang over us for some weeks.

“In that grand scheme of things I hope we come to realise what a splendid achievement this was.

“If success is judged on trophies then you would have to describe it as a failure but what a failure.

“It has been a glorious season and I wouldn’t have swapped the UEFA Cup run for anything.

“When I first came here I won the treble and then last season we won the league again but in all honesty, this has been the most memorable season for me.

“It has been epic, and the very fact that we went all the way to the UEFA Cup final while taking the Championship to the last day of the season says everything for the efforts of the team.

“They have shown phenomenal commitment and effort, as have the supporters, and it has been unforgettable.

He added: “I couldn’t be more proud of the players.

“They never gave up, not even after that defeat at Tynecastle when we looked completely out of it.

“They have been magnificent throughout the season and their efforts have been tremendous.

“It has been a journey that won’t be discarded easily and when we come to look back on it in time then I’m sure we’ll remember it as a terrific season.

“We played 13 UEFA Cup games, amassed 97 league points and lost the title on goal difference.

“I have never known such cruelty in football and I doubt that I will ever experience it again.

“Considering the number of messages of support and appreciation we have received then I think it has been a campaign we are all proud of and as far as I’m concerned the players deserve enormous credit.

“It has been a great effort and we have played some wonderful football over the last few weeks which is testimony to the ability and character within the team.

“We have played 60 competitive games this season and to put in that sort of performance at Kilmarnock after the heat and conditions of a UEFA Cup Final was remarkable.”