Just when Neil Lennon thought his players had turned a corner after a convincing win against Aberdeen last Sunday, they delivered one of the worst performances by a Celtic side in many years on Thursday night.
To lose 4-1 to a Sparta Prague side who were depleted through injuries and illness was embarrassing and one that should really hurt the players.
It was a must-win game for Celtic to keep their hopes of progression in the Europa League alive but, barring the first 20 minutes, Lennon himself best described the performance as "unacceptable".
He questioned the hunger and application of his squad and that is the biggest slight ever on a player. You can forgive players for having an off-night or lacking in certain areas but to criticise for a lack of commitment is the lowest of the low.
Lennon came out defending his players and his position last week and rightly so, but a tricky-looking trip to in-form Motherwell tomorrow is simply a must-win. Celtic supporters are rightly furious with their team and manager, meaning even a win at Fir Park is unlikely to appease them.
What started out as one of the biggest seasons in the club's history could collapse around them if they don't arrest the clear issues they have around the squad.
Across the city, Steven Gerrard's season so far seems to be in a better place but his managerial career is still in its infancy. In fact, it is only his third season but by far his biggest and most important. It is fair to say it's a season that will make or break him at Rangers as he battles to break the Celtic stranglehold over domestic trophies.
That is one of the main reasons the actions of George Edmundson and Northern Ireland international Jordan Jones will have infuriated him so much. There is so much at stake for him personally, the team and the supporters so the negative headlines at a crucial point in the season were viewed as a major distraction by Gerrard.
For the first time in years everything at Rangers looks aligned as a club and they lead the Scottish Premiership by an impressive nine points after the opening 13 games. Optimism is at its highest point for quite a while. The club and manager are clearly in a good place at the moment and the fact they made a quick decision to suspend both players immediately tells us how seriously they view the Covid-19 breach.
Gerrard recently said he has tried to give his players the best of everything from food at the training ground, pitches to train on and the best of travel to take away excuses they may have had. He will see this incident personally as a major let down.
Edmundson and Jones unfortunately will be remembered short-term among the Rangers supporters for the wrong reasons, attending a party when under strict protocols and threatening to derail the good work of the club and the medical staff.
Whether they still have a career at Rangers remains to be seen - ultimately that will be up to Gerrard.
Something Gerrard has reiterated throughout his spell as manager, though, is the need to trust his players. That doesn't just mean on the football pitch on a match day but in all aspects of their lives. The two lads in question will have to rebuild that trust of their gaffer before they can even think of having a long and illustrious career at Rangers.
There have been calls for both players to be sacked and never to don a Rangers jersey again but I think there has to be a period of calm before such decisions are made. I get there's a lot of emotion and anger around at the minute and some people can't fathom the ridiculous actions of the players. I can't either, but, as the players showed, acting impulsively isn't always the right way.
The bigger picture for Jones is that he will miss out on a potentially momentous night at Windsor Park on Thursday as Northern Ireland attempt to qualify for Euro 2020. Jones has always excited the Northern Ireland fans and we all know we don't have a large pool of players so for Ian Baraclough to miss a player who could win us the match is very disappointing.
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