IT would be wrong to go overboard about Celtic’s first defeat in any match since last November, but a result as momentous as this one still seems worthy of greater introspection.

What we are talking about, after all, is the Parkhead side’s heaviest ever home defeat in Europe, their joint-heaviest home defeat full stop.

And all at a time when their domestic dominance is more pronounced than ever.

So what does it all mean?

Well, obviously when you’re comparing two matches in isolation, certain circumstances can skew things. Celtic, after all, were coping with injuries to central defenders Dedryck Boyata and Erik Sviatchenko which meant Mikael Lustig had to move into the central area and a callow 18-year-old Tony Ralston exposed to the wiles of Neymar on the night.

Everyone is allowed an off night and luck can come into play too, although it could hardly be said that the score flattered the visitors.

But just perhaps a little piece of perspective on the matter would help. It will be ten years next month since a late goal from Scott McDonald sealed a 2-1 win against AC Milan, who just happened to be the reigning champions of this competition at the time.

For the record, an intruder leapt from the stands and on to the park that night too, aiming a playful slap at the neck of Dida, the Brazilian goalkeeper starting to run after the miscreant before tumbling to the ground as if mortally wounded.

By contrast, Paris Saint-Germain have never got past the quarter finals of this competition, and weren’t even domestic champions in France last season, even if recruiting Neymar for £200m, committing to another £160m for Kylian Mbappe and quietly enlisting the likes of Dani Alves means this was no ordinary transfer window for them.

So if this Celtic side are better than the likes of Gary Caldwell and Stephen McManus and Co there is only one conclusion which can be drawn: that Europe’s elite clubs are simply in a different stratosphere to the one they were in a decade ago.

The Parkhead side are improving year on year but Europe’s elite are accelerating away from them and don’t seem to be easing on the throttle.

The only other meeting between these teams didn’t end well either – a PSG side featuring Youri Djorkaeff, Rai and Paul Le Guen won home and away against Celtic in the 1995-95 Cup Winners’ Cup – but Tuesday must have been sobering to anyone feeling Scotland’s champions had realistic hopes of reaching the last 16 from this group.

Without access to the riches of the Premier League, the best Celtic can hope for right now is hanging on to the coat tails of the great and good in the Europa League, and trying to ensure that the goalposts are not yanked further away from them.

Another looming headache for the club is UEFA opening proceedings against them for the incident whereby a supporter entered the field of play to aim a fresh air swipe at Mbappe. The French prodigy sidestepped it with a minimum of fuss but Celtic will be unable to dodge action from the continent’s disciplinary body on this one.

All the club got back in 2007 was a £25,000 fine while Dida ended up with a one-match ban, but with 11 various misdemeanours on their rap sheet I fear the worst this time around.