Celtic left the Highlands last night on the back of a lament.

It may seem somewhat churlish to suggest that there is more learned in time of adversity given some of Celtic’s forward play against Inverness and the performance they brought out of Inverness keeper Owain Fon Williams.

But it was a familiar refrain that cost them two points -a soft centre despite making enough chances to win three games.

If they were to take anything out of this one it is simply that they need to be tougher when it comes to seeing a game out.

Read more: Celtic boss Brendan Rodgers: Scott Sinclair right on songGlasgow Times:

And while nearly all that Brendan Rodgers has touched in his early months at the club has turned to gold, there has been a reminder this week that this is still a work in progress.

And nowhere more so than between the sticks.

Dorus de Vries has taken the gloves from Craig Gordon but does not look to be the answer.

Read more: Foran wants refs to show more 'bravery' after big call goes against Inverness

Celtic have yet to return a clean sheet from their opening five league games this season and while they seem a safe bet for multiple goals, there remains a fragility at the back.

Barcelona scented blood and even in Inverness, as Celtic created enough chances to put this game firmly to bed, there was always a feeling that just one fleeting chance would blot the copybook. So it proved.

Those who like their football with a little ying to their yang, though, may have felt there was some justice when substitute Alex Fisher’s goal levelled a game that had looked out of reach of the hosts for the bulk of the second period.

Erik Sviatchenko was fortunate to remain on the park in the opening period when, with the score levelled at 1-1, he tripped Ross Draper as the striker did what all forwards are taught to do and ran across his path to invite the foul.

The player went down under a clumsy effort from the Dane, but while the only ambiguity seemed to be whether it was on the line or inside the box, Celtic escaped without sanction.

No penalty or free kick and no red card either.

From there on in, though, Celtic turned the screw.

Tom Rogic had opened the scoring for Celtic after just 17 minutes, but while the Aussie would have been pleased with what was a decent finish, it was Kieran Tierney, the architect of the goal who also deserved credit for the move.

Billy King levelled for Inverness with a looping finish that ought to have been better dealt with by de Vries, before Scott Sinclair penned his own note into Celtic’s history books as he levelled a tally of scoring in his first five league games, a record set by the inimitable Jimmy McGrory, the club’s greatest ever goalscorer.

It overtook the previous best by Stevie Chalmers – the Lisbon Lion netted in the opening four campaigns in ‘64/65 – but even at this early stage of the campaign it easy to see what Sinclair adds to Celtic.

It was all there in microcosm; the pace as he collected just over the halfway line and started his run, it was there in the clinical composure of the finish.

He almost added to his tally with a decent effort deep into the second period but there can be no doubting the manner in which Sinclair has given Celtic an edge in the middle of the park.

While it easy to see just why Rodgers was so dogged in his pursuit of the player, the same keenness to rush in de Vries does not seem quite so apparent.

The keeper displaced Craig Gordon a few weeks back when he took his place before the international break and has been there ever since.

However, give then tentativeness with which he has kept goal – he has yet to register a clean sheet for the club – the question remains whether or not he will remain in the position as the months go by.

Read more: Celtic boss Brendan Rodgers: Scott Sinclair right on song

Celtic will come out of this one not so much as feeling deficient, as they did leaving the Nou Camp, but rather in lamenting a series of missed chances.

Three times Celtic hit the woodwork in the second period – Moussa Dembele, Sviatachenko and Tierney all watched shots bounce back off the frame – while Inverness keeper Williams performed all sorts of acrobatics to keep Celtic at bay with a number of fine stops.

Even at the death and with Fisher having snatched a leveller entirely against the run of play for the Highlanders, he retained his focus to hold a Dembele deader as Celtic looked to fashion a late show.

There had been similar stops to deny Tierney and Dembele, while McGregor had incurred the wrath of Rodgers in Celtic’s technical area after he had gifted possession at one point with Dembele looked to collect and push forward.

It wasn’t the only time the Celtic manager had cause to lift his eyes heavenwards and curse events in front of him as Inverness stunned the Parkhead side with their only effort of the second period that brought them a point.