The option to have the day off was open to all, and has been used by the Hoops in previous years to allow them to travel to play lucrative friendlies against Real Madrid and Liverpool.
This time, there was no glamour game, no healthy cheque to collect.
But the down time did provide something perhaps even more valuable to Ronny Deila and his players - the opportunity to draw breath and reflect on what has been the most headline-making start to a season in living memory.
By the time they do start the defence of the title, at McDiarmid Park on Wednesday, they might just be able to have returned their eye to the ball and mind to the most important business of the season - making it four-in-a-row.
The high drama surrounding the 6-1 aggregate defeat to Legia, then re-instatement to the Champions League qualifying process, followed by the sale of Fraser Forster to Southampton for £10million, will have brought home to Deila that this is no ordinary club, and that he has taken on no ordinary job.
He has become aware that anything which does not run to plan is considered a major crisis, generating extreme reactions which perhaps do not sit easily with the typical Scandinavian even-keel philosophy on life. He now knows there is no grey, only black or white - which is how results are recorded.
Deila - who took in Dundee United's 3-0 victory over Aberdeen at Pittodrie yesterday - also knows that patience is a virtue, but not a luxury afforded Celtic or the club's manager.
The disquiet shown by some sections of the support at Murrayfield and in phone-ins and online last week after they thought they had witnessed their side meekly exit the Champions League last at the hands of Legia Warsaw will have struck deep in Deila's psyche.
The exit of Forster a few days later amidst talk from the manager of accepting the club's need to keep a wage ceiling in place, even though it heavily inhibits the need to recruit the ready-made quality the team now clearly needs, is further trying the patience of those who believe they are watching the club they love swell their finances but at the cost of any chance they might have had of reversing a downward spiral.
Deila will today bring in Aston Villa winger Alexsander Tonev on a year-long loan deal with an option to buy, and, by 11pm tonight, the deadline for delivering other new players he insists he wants for next week's play-off against NK Maribor will have passed, though there is provision in those all-important Uefa rules to register one more signing up to 24 hours before the first game in Slovenia.
By then, Celtic need to show the poor performances in the two ties against Legia have prompted a massive improvement throughout the team.
Six points on the board from their opening two SPFL games, against St Johnstone on Wednesday and Dundee United on Saturday - when the team will return to Celtic Park and Fergus McCann will belatedly unfurl the championship flag - are a must if the supporters are to accept the difficulties experienced in Europe in the opening few weeks of the campaign were simply down to ring-rust and the manager's message taking a few matches to get across.
Deila's credentials are being scrutinised even more than when he was first plucked from left field to succeed Neil Lennon.
How he gets his players to respond following the trauma of the defeats to Legia - and Uefa's intervention does not alter how poorly they competed - will be taken as huge indicator of what he can bring to what is a very demanding job, even when things are going well.
DEILA has his own confidants whose counsel he will seek as he considers what has transpired in the short time he has been at the helm, and what he needs to do to accelerate the progress he needs to make.
They will be able to sympathise, if that's what he wants. But they will not be able to empathise. You do indeed have to walk a mile in another man's shoes to be able to do that.
So perhaps Deila would benefit from spending some time in conversation with the man who has just vacated this hottest of hot seats, Lennon.
While he waits for the job offer which presents the challenge Lennon now believes his career needs, he has been a pained spectator of the trying time his successor has had to endure.
Lennon has found it easy to supply the words to best summarise the situation, and tough to keep them to himself as he articulates what so many on the outside looking in now feel.
"It's sometimes better to be lucky than good," he mused of Celtic's good fortune at being re-instated to the Champions League, a repeat of what happened when his side was knocked out of the Europa league by Sion in 2011. Back then, he led his squad into a group stage which saw them learn how to compete at European level, information they used 12 months later to qualify for the last 16 of the Champions League.
Whether or not Deila and his players can make as much use of their second chance, the games against NK Maribor will tell. Lennon hopes they can and added: "They have got a get-out-of-jail-free card - and I hope they use it."
The pressure is on all of them to ensure they do because crashing out of the Champions League qualifiers once is bad enough. To do so twice in the space of a few weeks would create a massive backlash.
It was Uefa intervention which got them back in after Legia were shown to have broken the rules.
But Efe Ambrose - whose sending off in the first game in Warsaw was pivotal and who was suspended for the return at Murrayfield - reckons it went even higher than that.
"What can I say other than to thank God," said the Nigerian. "It was divine intervention that saw us back in. We will take our chance and utilise this second chance to the fullest."
LENNON, however, recognises it is actions not words which count, and appreciates just how tough life can be for any Celtic manager - not only one just through the door - at this early stage of the season.
"The Champions League qualifiers are the most important games of the season for Celtic, and they are the first games, so they are a cup final," he said.
"Ronny hasn't had enough time to put his stamp on the squad, and I totally understand that. But they have got a huge, huge slice of luck here, and they've got to maximise it."
Not surprisingly, Maribor have other ideas. Having seen how easily Legia scored against Celtic, and denied them more than a handful of half-chances over the two legs, the Slovenians smell blood.
Legia still believe it is on the hands of Celtic, who they believe should have made some kind of plea for clemency on their behalf to Uefa after their Swiss delegate spotted the rule infringement. That is as naive as it is unrealistic. Uefa's rules clearly state the match must be forfeited and awarded as a 3-0 victory for the opposition.
This is not at the discretion of the opposing team, and Uefa's rules do not make any provision for a club to offer to step aside and let a rule-breaker go through.