Having achieved one of the greatest results in the club's history against Barcelona in what was also heralded as the best atmosphere at Celtic Park for many years, it was always going to prove an impossible task trying to avoid the subsequent comedown from such a momentous moment.
And so it proved. Just days after inflicting a sensational 2-1 defeat of the Spaniards in the Champions League which attracted headlines around the world, Parkhead was a far more subdued arena for the visit of St Johnstone yesterday afternoon.
Instead of playing in front of a packed out crowd that could be heard for miles, there were large holes in the stands and the lack of enthusiasm from the home crowd was reciprocated on the pitch as Neil Lennon's players seemed to go through the motions.
But how can you be too critical of a side that has restored Scotland's battered pride within the footballing world with their incredible efforts on the European stage this season?
With the embarrassment of Rangers being liquidated and the Scotland national team's dismal start to their World Cup qualification campaign not exactly promoting football in this country in a good light, Celtic have successfully managed to make amends with their Champions League exertions.
Simply qualifying for the group stage of the competition was a massive achievement for Lennon for financial reasons just as much as football reasons. However, it is the way they've handled the platform that has rightly earned them plaudits.
Starting off with a draw at home to Benfica before securing a first away win in the competition has been followed with a heartbreaking defeat in the Nou Camp before the stunning victory last week over the Spanish giants in the East End of Glasgow.
So, with that in mind, the Celtic supporters will be willing to accept below-par performances and poor results in the league at this stage of the season.
Further into the campaign and still not leading the way in the SPL, it will be a different story. But for now such results will be tolerated.
Under normal circumstances, drawing 1-1 at home to St Johnstone a week after blowing a two-goal lead to end up sharing the spoils away to Dundee United would have earned the Celtic players a mouthful from Lennon when they reached the home dugout.
The draw now means Celtic occupy second place in the SPL with Hibs leading the way, although a victory in their game in hand against Dundee United would see the defending champions return to pole position in a title race they were, and are, expected to romp.
Lennon admitted the efforts from his players during the week seemed to have taken their toll as he avoiding ringing the changes.
"There was no spark," he said. "They looked really flat and sometimes there's not a lot you can do about that. A few of them were just a bit short and they shouldn't have been.
"You're looking for that wee spark and Tony Watt gave us that but some of them were dead on their feet in the dressing room at the end. It's the second time in two weeks now we've taken a lead and conceded it and that's disappointing.
"We rested them as best we could. Mentally, I'm sure the game against Barcelona took a lot out of them and there's no doubt the physical side of it they are sort of struggling with a wee bit at the minute. The players that played the other night gave us everything again but there was just that bit of flatness about us.
"I accept that but I'm not happy about it. The squad's getting stretched but that's not an excuse and we have already played maybe nine, 10 games more than any other team in the country. St Johnstone have had a full week to prepare for this game. We had half a day."
Lennon elected to go with exactly the same starting line-up he fielded against Barca with the exception of Scott Brown's inclusion instead of Mikael Lustig.
Charlie Mulgrew moved to full-back and Adam Matthews switched from left-back to the opposite flank.
But despite enjoying most of the possession Celtic were sluggish and the only player who ever looked likely to do anything special was Kris Commons.
At the interval, Miku made way for Watt and the young striker then scored with what was his first touch of the ball immediately after the restart.
Celtic, however, failed to build on that with clear-cut opportunities in seriously short supply. And, like the previous weekend, they found themselves being pegged back as Nigel Hasselbaink made them pay for not clearing their lines to equalise for Saints.
There was to be no late rally from Celtic though. Exertions against Barca had obviously taken their toll and denied them the chance to press for a late winner.
There is plenty of time left for Celtic to flex their muscle in the championship race – right now the Champions League takes priority.