SHOCKING: Shell shocked celtic star speechless after champions league humbling - You Need To See This

Sinisalo has not shied away from recognising the extent of the collapse, maintaining that fans who made the trip to support Martin O’Neill’s team deserved much better. He said, "Obviously it's raw. I’m kind of speechless in a way.

"I'll try though because I don't think the people coming here to support us deserved that. Obviously it's unacceptable, and we're all very speechless about what's just happened."

The Finnish keeper dismissed complacency as the reason for the turnaround, but acknowledged that LASK’s first goal was pivotal. He said, "We scored the first goal and you're thinking, ‘four-goal lead, that's it’. They get one at a crucial time for them, which kind of shifts the momentum."

Sinisalo also admitted that Celtic’s demotion to the Europa League was justified. He said, "I've had a minute to myself and thought, is that the case?

"Tuesday just felt like one of those nights where everything seemed to work for them. We need to find a reason why that was and come back stronger."

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The 24-year-old believes Celtic moved away from the style of play that had given them control of the tie, becoming too direct against a physically strong LASK side. He said, "I think we lost a bit of the identity of the team that we want to be. We want to be a passing football team.

"They're big, they're strong. If we start going long, it's kind of playing into their hands a little bit."

Sinisalo is aware that the Celtic squad must now face the inevitable backlash after what he describes as an unprecedented result. He said, "No, you can experience losses, but you can't experience anything like this. You can't write stuff like this.

"It's not easy, but we'll come back stronger. We’ll regroup: we've got experienced pros in the changing room who have a lot of experience. They've been here a long time and know what's going to come at us.

"That's completely fair. People are entitled to say that. We've got to take it as a group and be better, ultimately."

Sinisalo refused to make excuses, acknowledging that Celtic simply weren't good enough. He said, "There's no need for me to come and say anything else. It's not what people would want to hear. I'm not going to come here and give you excuses.

"We've just not been good enough and that's why we're a team now in the Europa League."