Defeat to Livingston was as abject as any in recent memory. To be comprehensively out fought and out thought by a team of players that would do well to hold their own in English League Two was an eye opener.
Much has been made of playing on artificial surface and also of playing a few days after a (home) European tie.
Does the data support either of these as mitigating factors?
Playing on Plastic
It is increasingly common for smaller clubs to install all weather pitches as a means to generate income throughout the year from the community, and to reduce the overheads of grass pitch maintenance. It is perhaps understandable for clubs with minimal budgets. In Scotland there are not enough clubs with 10k+ average gates to not have smaller community clubs in the top flight.
Whatever the merits of the arguments, the current reality is Celtic get exposure to playing on artificial surfaces both in Scotland and in Europe.
To compare Celtic’s form on such surfaces, it is necessary to compare to Celtic’s away form overall.
I have taken all Celtic away matches (not including those at neutral venues as Celtic do not play any neutral ties on artificial surfaces) for the last 6 seasons and compared it to their record on artificial surfaces.
Pts% is the key metric here. This assigns 3 points for a win and 1 for a draw to every match irrespective of the competition and assesses the % points Celtic won over those matches. It gets around the weakness of Win % which ignores that a draw is a legitimate result.

Since 14/15 Celtic have played 153 away matches and average 65% Points%. As an aside, I discovered Deila’s away record (66%) was better than Rodgers (63%). Anyway.
On plastic, Celtic have played 26 matches over the same period and average 67% Pts%.
So, simplistically, Celtic’s record away on plastic is slightly better than their overall away record over the same period.
It should be restated that it is generally smaller teams that have artificial surfaces so this includes wins over Albion Rovers, East Kilbride and FC Stjarnan (but also Kilmarnock, Astana and Molde).
My conclusion is: you cannot blame the plastic for the Livingston debacle.
European Hangover
Playing Thursday / Sunday is demanding especially if travel is from the far reaches of what UEFA classify as “Europe”. That wasn’t the case here.
Nevertheless, I compare all Celtic matches post a European tie within 3-4 days with their record in all domestic matches over the same period. The reason for only including domestic matches is that all post European matches are domestic.

Since 14/15 Celtic have played 243 domestic matches with a success rate of 82% points.
Post European ties, Celtic have played 60 times and their Pts% is 81%.
I am not calling that significantly different but let me know if you disagree.
A further aside is that post Europe Celtic have played 29 away games, 6 on neutral grounds and 25 home matches.
The conclusion, however, is that in Scottish football, Celtic perform broadly the same whether they are coming off the back of a European match or not.
Summary
Sunday at Livingston was awful in every way with no redeeming features. However, given Celtic have a slightly better record on artificial surfaces than grass, and that their record coming off a European tie is almost identical to their overall domestic record, then the excuses of pitch and Europe don’t hold.
Players and management have two weeks to ponder what went wrong before the next assignment. As it is in the realms of player and management performance where the necessary corrective actions lie.