IT seems ludicrous on the face of it to suggest that with a potential back-to-back treble within touching distance there would be murmurs of discontent around Celtic Park, but there is no doubt that one or two dissenting voices are now being heard.

The goalless draw with Dundee on Wednesday night was the latest in a long line of uninspiring evenings the Celtic supporters have had to sit through this season. I can almost hear the tiny violins playing in sympathy from supporters of other clubs, but there is no doubt the entertainment being served up by Brendan Rodgers’s side has dropped a level or two during this campaign.

In some ways, after the incredible standard they had set last season, that was always likely to be the case. They scored in every single one of their league matches during their ‘Invincible’ season, a remarkable achievement that was always going to be nigh-on impossible to match. Even still though, the drop-off in terms of their goal threat has been significant.

Last season, Celtic scored 106 goals in their 38 games in the Premiership, but with six games remaining this year, they have netted just 62. They have had four goalless draws, with three of those coming in their last six league games.

So, there is no doubt that the goals haven’t been flowing for Celtic the way they once were, and when you compare some of the individual stats for some of the key performers last season it is easy to chart where this decline has come from.

There have been injuries of course to the likes of Moussa Dembele, Leigh Griffiths and Stuart Armstrong at various points in the campaign, but those players aren’t so far away from playing the same amount of games as they did last year, and all have posted lesser returns.

Dembele had 17 goals in 30 league games last season, but has just eight from 22 games this time around. Griffiths had 12 from 23 last season, compared to just eight from 21 Premiership appearances this year, while Armstrong has scored just three times from 24 league appearances this term compared to 15 goals in 32 games last season.

Scott Sinclair is probably the player who epitomises the decline in Celtic’s output the most, with just nine goals in 29 games compared to 21 from 35 as he swept the player of the year awards in his debut season. Again, he is a victim of his own success, with expectations around him sky-high after what he achieved last season, but even though he has done well in spells, he has largely been a shadow of the player he was and the fall in his standards has been starker than expected.

Of course, there are also mitigating factors from outside of the club to consider. The truth is that while Celtic have regressed, the others have improved, and the league is certainly stronger this year than it was last. Teams have found ways to cause Celtic problems, whether that is by pressing them high as Hearts did to win so emphatically at Tynecastle, or by containing them as Kilmarnock did to win at Rugby Park, and they know that the Celtic defence can be got at too.

The shedding of their long unbeaten record has resulted in a loss of Celtic’s veneer of invincibility, and teams have found this year that being organised and defending well against Celtic can get them a result. They have lost that edge, the desire that pushed them over the line so often last season as they looked to keep up their unbeaten record and resulted in them scoring so many late goals.

And another factor that has resulted in them losing that edge, is that while the gap between the best side in the league and the rest has narrowed, there is still a vast enough chasm between them and the eleven others that means they are 10 points clear with six games to go despite all of those dropped points along the way. Without any sort of credible challenger to their title, and with no unbeaten record to maintain, the incentive they had to keep churning out wins is no longer as strong.

I am a little surprised that the likes of Patrick Roberts and Charly Musonda haven’t been given more game-time in a bid to freshen things up and to inject a bit of hunger and creativity into the Celtic team, qualities which have been missing on more than a few occasions this term. I think that the fans would like to see more of them, as well as the likes of James Forrest have done carrying that burden over the course of the season.

As ridiculous as it may sound in normal circumstances when a team is in the position that Celtic are at this stage of the campaign, there is an argument to say that if they do fail to deliver the Scottish Cup and the treble, their season may be perceived to have been somewhat underwhelming.