THE task awaiting Celtic at Parkhead in their opening Champions League group game against Paris Saint-Germain tomorrow evening is a daunting, some would say nigh on impossible, one.

They must overcome opponents who broke – actually, make that obliterated – the world transfer record this summer when they paid Barcelona an utterly obscene £198 million for Brazilian forward Neymar.

They must get the better of rivals who will, despite the anticipated absences of Angel Di Maria and Thiago Silva due to injury, still be able to field Dani Alves in defence, Javier Pastore in midfield, Julian Draxler out wide and Edinson Cavani and Kylian Mbappe up front. No pressure then.

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But defying seemingly insurmountable odds has been done before – and not just in that famous 2-1 triumph over Barca back in 2012 either.

There was a time not so very long ago when Celtic would go into a meeting with any club in Europe, no matter how expensively assembled, regardless of how renowned a name, at home with complete confidence.

The likes of AC Milan, Barcelona, Bayern Munich, Juventus, Liverpool, Manchester United and Porto, among others, all rocked up in the East End of Glasgow expecting to coast to straightforward victories only to have their hopes spectacularly scuppered.

Stephen McManus, the former Celtic centre half who is now on the coaching staff at Motherwell after retiring from playing last month, was involved in a fair few of those epic evenings.

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Most memorably, he scored in a glorious 2-1 win over defending champions Milan, Dida, Alessandro Nesta, Massimo Ambrosini, Rino Gattuso, Kaka, Andrea Pirlo, Clarence Seedorf, Filippo Inzaghi et al, on a raucous night at Parkhead back in 2007.

McManus believes Brendan Rodgers’s side is back operating at the same rarefied level as they were when Martin O’Neill, Gordon Strachan and Neil Lennon were in charge and can surprise a few doubters in their opening Group B game against a team who have been installed as joint second favourites to win the tournament by many bookmakers.

He is hoping his old club pull off a triumph and give the whole of Scotland, buoyed by the unexpected resurgence of the national team in their World Cup qualifying campaign this year, a lift.

“Anything is possible,” said McManus as he looked ahead to the visit of the French champions. “Of course, it is a difficult task that Celtic have got, but they are in there, they have done the full country proud.

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“It is difficult for Scottish clubs. Look at Aberdeen, St. Johnstone and Rangers all going out in the early rounds. I think we need to do all we can as a nation to give our clubs the best possible chance to be successful in Europe.

“But Celtic have been terrific and are flying the flag. It gives every club benefits. They get money from it. It is just great to have Celtic back on the map for everybody, for supporters, for the media. There is a real buzz around these games. You can get excited about them. They are terrific occasions.

“The Celtic players will be going into every single Champions League game knowing and believing they can win. At home especially. Whoever it is, Anderlecht, Bayern Munich, PSG, they will be looking to win at home.”

He added: “Under Brendan, they are back to where they were when Martin O’Neill, Gordon Strachan and Neil Lennon were in charge. They have gone the season unbeaten and have started back where they left off.

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“Motherwell played against Celtic in Ronny Deila’s last game when they received the league trophy at the end of the 2015/16 season. We weren’t really on it that day and Celtic were in party mode and played well. But I always felt with that side that you could get at them if you were on your game.

“But Brendan Rodgers has since come in and turned things around. We played them in the Betfred Cup last season and we were right at it, played really well, and could not get anywhere near them. They were that good. They have got pace, quality, enthusiasm, tactical awareness from the manager.

“In the game here at Fir Park that we played against them last season we were on top (they led 2-0 and 3-2) and looking good. Brendan Rodgers, John Kennedy and Chris Davies, between the three of them, changed things. They ended up coming back and winning 4-3. They are a very, very strong side just now and there is no reason for them to fear anybody in the Champions League.”

The celebrated win over Carlo Ancelotti’s star-studded side 10 years ago next month went a long way towards atoning for the excruciating defeat which Strachan’s team had suffered in the last 16 of the Champions League the previous season.

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McManus and his team mates were only beaten 1-0 on aggregate after Kaka scored in the third minute of extra-time in front of a crowd of 65,000 in the second leg in the San Siro.

Asked what it had felt like to run such redoubtable adversaries so close in what had been Celtic’s first foray into the knockout rounds of Europe’s premier club competition, the former Scotland defender admitted: “At the time, you are definitely scratching your head a wee bit.

“To say that you have shared a pitch with them was great. But you competed with them. Gordon was always stressing that, no matter what happened, make sure you compete.

“To take that AC Milan team to extra-time over two games was no mean feat. They went on to win that year (they beat Liverpool 2-1 I the final in Athens). They had top, top players. I don’t think at the time people gave us any credit.”

Should Celtic get a result against the multi-millionaires of Paris-Saint-Germain tomorrow– as Stephen McManus is optimistic they can do – they will deserve every bit of praise they receive.