After throwing away a 4-0 aggregate lead, Celtic will now compete in the Europa League.

When Callum McGregor eviscerated his own team-mates in the wake of Celtic's stupefying Champions League collapse against LASK, he delivered their one coherent moment of a spineless night. In branding his fellow players "passive" and "scared" and in then sending a telling shot across their bows - "now we'll see what people are made of" - it is hard to recall him being so full of fury after a European game.

And there are plenty to choose from, plenty of dark nights, plenty of embarrassment, plenty of soul-searching over many years. For close to a decade he has been Celtic's best player, a near ever-present. That longevity has brought him many trophies, but he's been around for many mortifications, too.

Where losing a 4-0 advantage ranks in the pantheon of Celtic failures is a moot point. What is unarguable is that it was a total capitulation, a feeble collapse in the face of LASK's physicality and desire and belief.

O'Neill takes responsibility after Celtic's latest European capitulation.

Exhausted & fragile - how Celtic's capitulation unfolded. Celtic blow four-goal lead to LASK in Champions League collapse.

The Celtic captain called his players "scared" when winning 4-0. No media hatchet man could come up with a more damaging word to describe what happened out there.

McGregor has been through the European mill. He was there last season when Celtic's fecklessness saw them go goalless for 210 minutes against the popgun boys of Kairat Almaty before failing to score from three of their five penalties in the shootout. He was there for the 7-1 against Borussia Dortmund and the 6-0 against Atletico Madrid. He's a survivor of the Champions League play-off exit to Midtjylland and the pair of 4-1 losses to Sparta Prague in the Europa League. He was around for earlier Champions League play-off exits against Ferencvaros, AEK Athens and Cluj. He's a veteran of the 7-1 loss to PSG and the 7-0 loss to Barcelona. He wears the scars as much as he holds the medals.

It is difficult, though, to recall him being as seething as he was on Tuesday night. He wasn't ranting - that is not his style. He spoke calmly which lent his words more power. He was raging in his own way. Raging at another exit, raging that when the chips were down too many of his fellow players panicked and allowed themselves to be overrun, raging at professional pride being trampled underfoot for all to see.

This video can not be played 'We're a million miles from the finished article' - O'Neill after Celtic's Champions League exit.

It was McGregor who opened the scoring on the night, a deflected shot and a 4-0 lead on aggregate. LASK had started well but that goal looked to all the world like a kick to their solar plexus. They had chances in Glasgow and they had chances in the opening minutes in Linz - and they were 4-0 down!

How many punches can one team take before they lose their fight? Many, as it turned out. Celtic were obliging, of course. Painfully so. We trumpeted their classy goals and their adventurous play a week ago and wrongly assumed that they had gumption to go with it. Big mistake.

When Benjamin Nygren's ridiculously loose pass led directly to LASK's equaliser on the night, the first signs of a wobble were visible. Thirty two minutes had been played and Celtic did not look wholly comfortable at 4-1 on aggregate. Mad, but true.

When they conceded again three minutes into the second half, there were a few jelly legs on show. Auston Trusty was culpable this time. Brushed off the ball. Swatted and 4-2 now. Trusty was poor, not the only one, but a point of real weakness that LASK went for.

Ten minutes after the hosts scored their second, they scored their third. Too many parts of the Celtic team were in full fright mode now. The slow death was picking up pace. Camilo Duran, the hero of the first leg, was reduced to a non-event. Kasper Hogh worked hard but with no impact. Passes went astray. Celtic were directionless. Everything fell apart.

Rabbits in headlights do not tend to look as lost as Celtic did when the pressure really hit. If McGregor was trying to put out fires in his own team he was failing. He could not cut through the tension. Martin O'Neill looked on like a man 10 years older than his true age. This was a shocking night for him. One of his worst in football, he said later. He took responsibility, but he cannot be alone in that. He emptied his bench in a desperate attempt to stem the flow, but his substitutions, five in 12 befuddled minutes, had zero impact.

Celtic did not have a shot on target in the second half of normal time nor in extra-time. They only existed as a man hanging off a cliff edge exists. There was only one way this was going to end. LASK's fourth goal might have come in the 90th minute but it was deserved. By that point they'd had 33 shots on Celtic's goal (they finished on 40) to go with the 20 from last week. It was a rout.

Cameron Carter-Vickers was hobbling about on one leg. Hogh much the same. Forward came the waves and Celtic tried to hold them back with a back four of Anthony Ralston, Dane Murray, Trusty and Liam Scales. The fifth goal was a mercy, and another Celtic player doing the wrong thing at the wrong time in the wrong place. For Nygren and Trusty read Luke McCowan. Hapless and helpless - and out of the Champions League.

The night meandered to its conclusion. LASK missed a penalty for 6-1 before Miguel Freckleton, recently of St Mirren, slalomed his way into the Celtic box and threatened, for a second, to score. All credit to Freckleton and his new beginning in Austria, but in flashes he was made to look like a serious player in his few minutes on the pitch. When that kind of thing happens it tells a story. Celtic were beyond disarray by then. Spooked, over-powered, out-fought, out-played. The smooth-running killers of last week in Glasgow was an optical illusion that hid psychological deficiencies.

Nobody could have predicted that they would fall in such a heap at 4-0, but they did. Celtic, quite obviously, need a back-up left-back to Kieran Tierney and they don't have one. They absolutely need, and this is no secret, a physical presence in the middle of the pitch, a player of stature in every sense of the word, a guy who would not be bullied as Celtic were bullied in Austria. They don't have one of those either. They have done good deals but not enough of them. They're in net profit in their transfer business this summer. The A-word - ambition - is going to get another airing.

When you finish a £40m match with a back four of Ralston, Murray, Trusty and Scales then, as a club, you have not done your work properly. Nobody did on the night, on the field and off. All those other defeats were incredibly costly in a financial but also in a self-worth sense. They hoped they'd left the Champions League drawing board behind, but they're right back where they were when Kairat and Midtjylland and Ferencvaros and Cluj and AEK were the ones inflicting the pain. Incredibly, another name has to get added to the list.

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