Aberdeen have an opportunity to leapfrog Celtic in the SPL fixture tomorrow afternoon at Pittodrie.
It is an acid test for Craig Brown's side – but it is also a significant match for the Hoops.
It has been a pretty poor start to the league season and although there are reasons that we can suggest for that, it is still time to start playing the league games the way that Celtic can do.
To me, a lot of it comes down to having the right kind of attitude. There has been no Rangers in the league which has obviously taken away an edge to proceedings, but at the same time, things are never cut and dried in football.
You don't win trophies because you are the favourite to do so, you win them because you produce the right level of performances.
Coming off the high of the Champions League and the win over Barcelona last weekend was always going to be a difficult one.
The atmosphere was jumping and going from that, it was always going to be a bit flat then at the weekend.
But that is when, as a player, you must produce something that sparks the crowd.
Few of us would really have envisaged that there would have been any kind of struggle at all for Celtic in the league race this season – and I have to say that I still don't.
I would imagine that there will be no real issue with them winning the championship.
But I do think that they need to start playing the way that they can.
Guys like Victor Wanyama, Gary Hooper and Kelvin Wilson have all made big contributions this season, but Celtic's strength is that they work hard to knit together and play as a unit.
The Champions League campaign has been fantastic and the results enjoyed by Celtic in the tournament have given Scottish football a massive shot in the arm.
Their form has been excellent, even if you include the qualifying games, but they now need to get to grips with the SPL.
Funnily enough, although many of us would attribute it to the fact that Rangers are not there to put pressure on them, this time last year Celtic were trying to chase down a 15-point deficit. It may be that, like last season, that they push on now and get stronger as the campaign goes on.
It is a big week now that looms for Celtic with tomorrow's lunchtime game at Pittodrie followed by the trip to Lisbon for the Champions League tie against Benfica. By this point in the campaign I suspect that most of us would have anticipated that Neil Lennon's side would have opened up a significant lead.
The strength of this Celtic side has always been that they have a good work ethic.
But they cannot afford to look at an opposing team sheet and play as though they just need to go out and turn up.
It is not a question of going into games thinking that they should win, but actually turning their mindset into going out and doing it.
The atmosphere at league games are never going to live up to the energy that is on display during the Champions League nights.
However, you need to get the right performances that get the reaction you want from the crowd.
Despite the poor league form, there is ample reason to suggest that Celtic will get themselves back on top and will go on to win the league.
But I do think that they need to start producing the kind of performances of which they are more than capable of in the SPL.