IT used to be said that at the Old Firm, you were never more than a defeat away from a crisis. These days, it appears not even a win can shield you from such talk.

After Celtic defeated Rosenborg on Thursday night, it would have been easy to forget that the Scottish champions actually won the game.

All of the fallout in the aftermath of the Europa League opener centred upon Celtic’s lacklustre showing, the bluntness of their attack and the debate over who should spearhead it. The man who finally lent a cutting edge to proceedings, Leigh Griffiths, appeared in no doubt as to who – in his words – was number f*****g one.

While it is important to recognise that this may very well indeed turn out to be a very handy three points in Celtic’s quest to qualify for the last 32, there was more than a hint of Griffiths’ late goal papering over some rather sizeable cracks in the overall showing from Brendan Rodgers’ men.

Suddenly, the formerly free-scoring Hoops are struggling to break teams down, and they came perilously close on Thursday night to recording their first back-to-back goalless draws since Tony Mowbray’s reign.

When Rodgers first arrived in Scotland, his Celtic team blasted 17 goals past their dazed opponents in the first five Premiership outings of the season. That had regressed to 12 goals in the same period last season, which was still a respectable tally.

Alarmingly though, the frequency with which they have found the net has fallen off a cliff in the opening weeks of this term, with just five goals being scored in five matches to date, and three of those coming over newly-promoted Livingston on flag day.

They have scored once in a home win over Hamilton, once in perhaps their most impressive performance of the season so far against Rangers when they were unlucky not to score more, and failed to find the net on the road in defeat at Hearts and in a goalless draw at St Mirren.

Sitting second in the table behind Hearts, it is hardly time for talk of crisis, but there appears to be some justified concern among the Celtic support not only at the number of goals drying up dramatically, but in the plodding nature of their play.

Make no mistake, the large home support that turned up on Thursday in defiance of any apathy that may have set in by facing a familiar opponent in a competition that is firmly the bridesmaid in their eyes were getting tetchy long before the end at what they were watching.

Celtic were moving the ball too slowly, and without enough direction. Kieran Tierney was the only player who wanted to take on his man and make something happen offensively, with the likes of Callum McGregor, Olivier Ntcham and Tom Rogic decidedly off-colour.

As for Odsonne Edouard, he will strengthen the case for Griffiths to start just as much as his teammate’s goals will if he turns in many more performances like the one he put in against the Norwegian champions.

He is still very young, and it should be taken into account that he is still hugely inexperienced when it comes to playing week-in, week-out at the top level. However, it appears from the outside that he is currently lacking the confidence and the belief that it takes to shoulder the responsibility of leading the line for a club like Celtic.

He has netted four times in 10 games this season, but he has now gone five matches without finding the net and never really looked like scoring against Rosenborg. Even when chances came his way in the first half, he showed a lack of conviction, and was rarely putting himself into dangerous areas when it mattered.

If Tierney is on a bonus for assists, then his young teammate might just owe him a few quid. Time and time again on Thursday evening he flashed the ball across the goal into areas where you would expect a predatory striker to be lurking. Instead, Edouard was usually posted missing.

Would he have gambled on Dedryck Boyata winning the header that brought about the opportunity for the winning goal? Not likely on the evidence of the rest of the match, and there must surely be a question mark in the Celtic manager’s mind over whether he should remove the £9million Frenchman from the firing line and give Griffiths the opportunity from the start he will feel he has earned on Sunday against Kilmarnock.

There is no doubting Edouard’s all-round talent, but he has some way to go to match the hunger of a goalscorer like Griffiths. The latter’s predatory instinct, could be just what Celtic need right now.