But, the good news for Neil Lennon, his players and the support which has followed them to Helsinki, Helsingborgs, Moscow, Barcelona, Lisbon and will turn up in numbers in Italy, despite their team trailing 3-0 to Juventus from the first leg, is that the Parkhead club will only be off the Euro carousel for 18 weeks.
They are romping away with the SPL championship, and the single Champions League qualifying place available to Scottish teams next season is already in the bag.
The bad news is that, despite Celtic's valiant efforts this season – their run to the Last 16 has secured a highly-impressive 20 points for the co-efficient table – Scotland has plummeted down the rankings.
Not only does it mean we have lost our second Champions League spot for the foreseeable future, but our champions will now have to enter the competition at the second qualifying round.
The draw for that takes place on June 24 – less than a month after the Scottish Cup final brings the curtain down on the domestic campaign.
By then, Lennon will need to have his players back in harness because the first leg of the second qualifying round takes place on July 16, with the return the following week.
The third qualifying round – the level at which Celtic entered this season – kicks off on July 30, with the second leg a week later.
By the time the knock-out round takes place, on August 20 and 27 – the final hurdle to be cleared before a Group Stage, and the millions that comes with it, can be secured – the Hoops' Euro campaign will be five weeks old.
All of which will require a lot of forward planning, as Lennon is acutely aware how vulnerable a team can be in the qualifiers if they are not sufficiently up to speed.
Harsh lessons were learned in his first go at this, losing to Braga 3-0 in the opening Champions League qualifier in 2010, then crashing out of Europe altogether a few weeks later when they were heavily defeated by Utrecht in Holland in the Europa Cup knock-out round.
Sion came close to halting Celtic in their tracks before they got into their stride last season, only for the Swiss club's flagrant abuse of the rules to hand the Hoops a reprieve.
Suitably warned, Lennon got it right last summer when an intensive build up in Germany and Holland during July put them in good shape to face Helsinki then Helsingborgs in the qualifying rounds for the Champions league.
They used this as a launch pad to win 10 points in the Group Stage and become the only side to reach the Last 16 after beginning their campaign in the qualifiers.
It meant an early recall for his players, many of who had already been forced into a short close season due to international commitments.
Georgios Samaras and Mikael Lustig were involved in the European Championships, while Victor Wanyama and Emilio Izaguirre were playing World Cup qualifiers, extending the previous season through to late June.
Having triumphed in the Africa Cup of Nations, this summer Efe Ambrose is scheduled to travel with Nigeria to the Confederation Cup, being staged in Brazil from June 15 until June 30.
WITH most countries scheduled to play World Cup qualifiers on the weekend of June 7 – Scotland are away to Croatia on that date – the chances are that the bulk of Lennon's team will only have a couple of weeks to rest up before they are recalled for pre-season training.
Europe has proved so important to the Parkhead club this season, in terms of income, profile and experience.
The thought that being inadequately prepared could see them crash out altogether before July had passed – there is no parachute into the Europa League for teams who go out of the Champions League at the second qualifying stage – is anathema to everyone at Parkhead.
So, the groundwork has already begun. With Lennon admitting they now need a miracle to continue in this season's competition, and the league race all-but run as they forge 18 points clear, only the Scottish Cup dates have to be ringed as of high importance.
The opportunity will be taken to allow the players who have carried the team for the bulk of the 42 games played to this point to enjoy some much-needed rest, in lieu of the full close-season which they will be denied.
The 'shadow' side which performed so well at Inverness last weekend can expect to be given further opportunities to enjoy the spotlight.
That can only benefit everyone at the club as battle-weary stars get the chance to recover and recharge, while men in desperate need of game time get precisely that.
The one dilemma Lennon has is what to do about the return game in Turin.
IT is not in his nature to accept it is a lost cause, though a miracle and couple of snookers are required to get them back into the tie.
But, pride is at stake, and the manager does not want a European campaign which has helped put the club back on the map to end in any kind of ignominy.
They have put another £5million in the swelling kitty, courtesy of Tuesday's game against Juve.
But, what might be even more valuable for the future is the experience gained from playing against such a seasoned and effective side.
That can be banked, and taken out with interest when the next European campaign kicks off.
Lennon knows that will be another tough road to travel, and understands that, for all the progress made this year, it will be a case of going all the way back to square one.
With the future of Gary Hooper and Victor Wanyama – watched by Arsenal in midweek – still to be resolved, the mana-ger could find himself trying to bed in new key players in those formative weeks of the season.
He said: "There are no guarantees on next season. We don't now what personnel we will have when the it begins again in July.
"It has been a great experience for a lot of the players. Even on Tuesday, it was a harsh experience, but one they should learn from."