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We'll give the final word to a despondent Martin O'Neill.

Scroll down to get more reaction from the Celtic boss, captain Callum McGregor and the pundits.

You can read Jack Herrall's match report here and visit our Celtic page for more.

That brings an end to our live text coverage on a scarcely believable European night for the Parkhead club.

For all the wrong reasons.

More from Celtic boss Martin O'Neill: "I think these games show you we obviously have a lot of work to do in that aspect [squad depth].

"These games are real, real tests for you and unfortunately we've failed that test tonight.

"I'm responsible for this one, but I don't know what's happened in the past.

"Naturally it took me a long time to get over the UEFA Cup final in 2003, but this was majorly disappointing. In the context of things, one was a final which would have been terrific to win, this was a qualifying game which we should have been able to get through.

"We know that we are a million miles from the finished article. That's absolutely true. I think we thought that anyway.

"The qualification for the Champions League is major. It's major in every aspect. Financially, for prestige, but we have to pick ourselves up. That's my responsibility again to do that.

"I think I said last week that if you could qualify for the Champions League there would be players wanting to come on that basis.

"That's not going to be the case, but we'll see. Tonight we came up well and truly short, particularly in the second half."

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Neil Lennon
Former Celtic manager on Amazon Prime

The lack of game management, the lack of real physicality and mettle - that's something you don't really point at these players often. But it wasn't there tonight.

Paul Barnes
BBC Scotland in Linz

Celtic’s players looked shell-shocked as they wandered over to acknowledge their travelling fans, only a handful of whom stayed beyond the full-time whistle.

And those that remained told their team exactly what they thought about that outcome.

A chastening night for the Glasgow side.

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Ready for some Europa League draw details, Celtic fans?

Thought so. Too soon.

Anyway, it's at 12:00 BST on Friday. We'll leave it at that.

You can hear more from Martin O'Neill on Sportsound right now.

He's talking at his post-match media conference.

Image source, SNS

Celtic manager Martin O'Neill tells Amazon Prime: "We scored a goal, missed two great opportunities, and then we gave them a lifeline before half-time, then one after it and they came roaring back.

"That's my team and that's my responsibility.

"At half-time even though we conceded a poor goal before that I thought we were still well in command of the game.

"It's hard to stem it when they are chasing the game, we can't get out for 10 minutes. We seemed to have weathered the storm then they scored to take it to extra time.

"I'm disappointed that we've conceded goals in the manner we did. It's my team, I'm responsible for it.

"These are tough games. I know it was a qualifier, but it felt like a Champions League game tonight.

"They're a fine side, but that doesn't matter. We should have been able to see it through. Talking about the squad, that's for another day.

"The players will be massively disappointed, especially because we took a three-goal lead here.

"I think it's a massive disappointment. I know we're playing in the Europa League, but that's a scant consolation this evening. There was a feel-good factor about and it's become a real disappointment tonight."

On whether this is one of his worst European nights managing Celtic, O'Neill adds: "It is absolutely.

"But I'd put it below losing the Uefa Cup final in 2003."

Need to do a double take every time I look up at the telly and see the final score.

Bonkers.

Celtic captain Callum McGregor tells Amazon Prime: "When you play like that you can't have any excuses whatsoever.

"When you go 1-0 up in the game and it still doesn't settle you, you can't have any excuse and that's on us.

"You fall at a big hurdle and these questions [on whether the squad are ready] are going to be asked. You can't lose by that margin then look for excuses elsewhere.

"This is what it's like to play at Celtic. You have to bounce back, you have to show a reaction and that's what Celtic are all about."

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We'll have more from the Celtic boss soon.

In the meantime, here's more from Callum McGregor...

"We should have been out of sight by half-time," says Martin O'Neill.

Celtic were four goals up. They were out of sight.

Stiliyan Petrov
Former Celtic midfielder on Amazon Prime

Everyone [is to blame]. They are all in it together. A big club like Celtic should be able to hold that out.

"Passive".

"Scared".

"You'll now see what people are made of".

Hard-hitting stuff from the Celtic skipper.

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Celtic captain Callum McGregor tells Amazon Prime: "We got what we deserved. We were passive all night.

"We looked scared to go and win the game.

"I didn't think we were that good in the first leg either. We scored at good times and got away with it.

"We have to suck it up. We apologise to our supporters and the club because there's no way we should lose that game.

"It's as much on the players as everyone else. You can't look for excuses elsewhere.

"You'll now see what people are made of."

Some seriously strong quotes from Celtic's captain coming right up...

Neil Lennon
Former Celtic manager on Amazon Prime

It looked to me as if Celtic were exhausted. Fragile in duels. It only looked like there would be one winner.

Huge credit to LASK. They battered Celtic tonight, physically and on the football side. It could have been more.

Take your point, Dave, but Celtic have spent a lot of money this summer.

Scott Brown
Former Celtic captain on BBC Sportsound

It was a fantastic start, you go 1-0 up, but that seems like forever ago. Now they've crashed out the Champions League and conceded five goals.

LASK outran Celtic in a couple of areas, the two up front were strong, solid and willing runners.

LASK deserve to go through with that performance. I feel for the lads because I've been in that situation as well.

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Twelve months ago, Celtic played out a turgid two-legged affair with Kairat Almaty. They were eliminated from the Champions League in humiliation.

This year was supposed to be different.

It's different alright. It's worse.