How do you retain interest for the rest of the season when the double has gone and all that's left is a title race in which you are so far ahead the rest of the teams involved would require sat nav to keep track of you?
This time last year, the massive excitement generated by the upcoming Champions League last-16 ties ensured everyone was playing to their very best, desperate to be involved against Juventus.
The League Cup had already been wiped from the club's radar, but the Scottish Cup was still a live target.
By contrast, the weekend defeat to Aberdeen means this campaign has been shorn of a genuine climax, and is in serious danger of becoming a process of completing league fixtures until the title is mathematically Celtic's for a third consecutive season.
Of course, the challenge of remaining unbeaten throughout the 38 SPFL Premiership matches, extending their clean sheet run in the competition, bursting through the 100-point mark, and possibly surpassing the 103-points record set by Martin O'Neill's side in 2001-02 remain as incentives.
But will they put posteriors on seats at Celtic Park? The truth is it is down to the players to find it within themselves to deliver the performances which encourage the supporters to attend - starting this weekend when St Johnstone come to town.
They can all take their lead from the manager who, despite the body blow which was exiting the cup so early, has a simple answer to the question: How do you keep it going for the rest of the season?
"We have to," is his unequivocal response. "You can't lose faith in the players on the back of one poor performance, although it was a pivotal game for us in the make-up of the season.
"But, no, you can't just turn your back on the players as quickly as that. We have to go again. It was the performance overall that was baffling.
"Far too many big players were well below the standard on Saturday."
Lennon is not just beating the drum on behalf of the ticket office. His remit is to get the best out of his players. And, in terms of the championship, there is no denying he has done that since day one of the defence of their title.
As a result, championship flag No.45 for the club is well on its way, their 21-point lead putting the Hoops on course to retain the trophy before the split.
Ironically, the ease with which they appear to be completing their No.1 priority has diluted the interest being shown in their achievement.
In some cases, it is even belittling it because the points advantage already built up gives ammunition to the snipers who claim there is simply no competition to Lennon's men in their shot at glory.
Which is why it has become more than a sideshow that they remain unbeaten for the duration.
It would mean it was not simply another title, but a special title, and tangible proof that progress continues to be made by a manager who, four years ago, picked up the pieces of a broken team and rebuilt a squad after Tony Mowbray's horror 10 months in charge.
"It's important we keep this unbeaten run in the league going," said Lennon as he continued to analyse what went so wrong in the cup last weekend.
"At the end of the day, you want to play in cup finals and you want to win them and you want to keep your season alive.
"I mean, we are 21 points clear and people are saying 'Well, that's that'. I think that's unfair because we have been magnificent in the league campaign. But the two cup competitions have been bitterly disappointing."
Lennon would have taken immense pride in joining Jock Stein and O'Neill at being able to say he led Celtic to a treble.
A misfiring display against Morton in their first League Cup tie of the season put paid to that this time around, though Lennon was not unduly upset by that defeat due to the fact his side was, at that point, in the middle of Champions League ties against AC Milan and Barcelona.
However, there was no such distraction when they lost to Aberdeen at the weekend, Europe having been over for almost two months by then, a mid-winter break enjoyed in the interim, and the team back in the winning groove.
Given how well they had been defending, a replay was the worst most feared might be the outcome of their fifth- round tie.
Perhaps the invincibility tag which was being hung around Fraser Forster and his defenders blinded them to the dangers Aberdeen brought south with them.
Whatever the reason for the lackadaisical defending, the price paid was heavy.
Lennon reflected: "After going so long without losing a goal, the manner of the two conceded was poor.
"We worked a lot on set- pieces, and analysed the way Aberdeen executed them. We knew they would hang Andrew Considine outside the box, and we knew set-pieces would probably be their best way of getting a goal against us. But we didn't deal with it. My two centre-halfs were very, very poor on Saturday."
It can't be ignored, however, that Celtic still had 40 minutes in which to recover from the shock of going behind to retrieve the situation.
But the threat they posed to Jamie Langfield in the Dons goal was minimal.
Virgil van Dijk, Kris Commons and substitute Leigh Griffiths did have chances, the best falling to the Dutchman from a cross from the right, but none of them managed to get an effort on target.
Along with the goals conceded, Lennon has also been looking closely at why his side failed to fire after Anthony Stokes' cool and clinical finish in the opening minutes.
"To be fair, James Forrest put in about five or six really good crosses, and that's why we went with Amido Balde at the end because they are not as strong at the back physically," said Lennon.
"But the final ball was poor. The final finish was poor. I think we only had one shot on target in the second half, and that was outside the box."
Food for thought as they face the prospect of months starved of genuine excitement.