It is not just sweltering temperatures that have had Celtic in a sweat this past week.

A roasting from West Ham on Saturday did little but highlight the defensive deficiencies that have plagued the club over the last year but while the short-term projection may look threadbare ahead of this week’s trip to Denmark with few options at the back, at least there are visible solutions to that area of the pitch.

Christopher Jullien’s knee ligament damage has left him on the sidelines since last December but his return in September along with the imminent availability of new signing Carl Starfelt will offer options as the season goes deeper. That is not to detract from a compelling argument regarding further reinforcements in that department.

Of immediate concern, though, is the goalkeeping situation.

At points last season Vasilis Barkas, Scott Bain and Conor Hazard were all custodians of the position. Trouble is that of the trio there wasn’t one who offered a convincing argument to keep it.

Barkas had two decent saves against West Ham before the roof started to fall in on Saturday. And the problem for the Greek keeper is that he is suffocating in what may prove to be an intolerable pressure now.

The perennial complaint about Barkas is that he doesn’t and hasn’t made enough saves of note. It is a narrative that has gathered pace since the early days of an unconvincing Celtic career.

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Recent polls regarding whether he should hang onto his position would hardly offer a vote of confidence. Yet, if any reader here has ever laboured under the watchful eye of a superior who had little faith in their ability to deliver and perform, then there will be some sympathy on a human level for the keeper.

The expectancy of failure tends to become a dreadfully self-fulfilling prophecy. And so it is now that he has to prove his capabilities while knowing that there is little trust in his ability to do so among supporters. Trouble is, the only way to salvage the erosion of confidence is to produce on the park. Words, encouraging or otherwise, from those around him will have far less currency than a string of decent saves.

There remains conjecture about Fraser Forster and the potential of a third stint at Celtic – the smart money might be that he is using Celtic as leverage in his dealings with Southampton amidst talk of a significantly reduced deal – but for the immediate future, the goalkeeping question isn’t going to change significantly.

Barkas now is faced with a challenge that is two-fold and significantly harder than when he first walked into the club; he has to turn an overwhelming tide of public opinion while also showing a personality big enough to cope with what is an almighty pressure.

It would be difficult to read too much into the change of keeper at the break on Saturday as this would be fairly common practice in pre-season friendlies. It offers no real clue as to whether he will keep his place for the second leg of the club’s Champions League qualifier in Denmark on Wednesday night.

There is clearly a goalkeeper in Barkas somewhere. Having played at Champions League and international football there is unquestionably an ability. The big question for Celtic now is whether he can rediscover the confidence that allows that to surface while at the club or whether he needs to write off this chapter of his career, a chapter that came around in the midst of the most testing and unusual global circumstances.

But how Barkas and Celtic could do with a big performance right about now.