THE financial repercussions of Celtic’s failure to qualify for the Champions League group stages for the second successive season are fairly straightforward to calculate.

Just how costly the defeat to Malmo in the play-off on Tuesday night proves to be for their manager Ronny Deila, though, is less clear cut at this stage.

When the Parkhead club lost to first Legia Warsaw and then, after their conquerors were subsequently penalised by UEFA for fielding an ineligible player, NK Maribor in the qualifying rounds last year there was bitter disappointment and deep unhappiness among the support.

But there was also an understanding that Deila, the 38-year-old who had just arrived from Stromsgodset in his native Norway, needed time to establish himself at the Glasgow club and familiarise himself with the idiosyncrasies of Scottish football.

He duly received that and led his side to the Premiership title and League Cup as well as into the knockout stages of the Europa League where they performed admirably against Inter Milan both at home and away in Italy before exiting.

Yet, Deila has now been in his job for over a year. What is the Celtic hierarchy and fanbase, then, to make of the abject display and hugely costly failure in the Swedbank Stadium? There is no question of them taking the same lenient attitude towards the man who was ultimately responsible.

His side was exposed defensively by spirited but extremely limited rivals, failed to threaten the opposition goal to any great degree, lacked discipline and even appeared to struggle with the ferocious pace of an intense encounter.

Much has been made of the Scandinavian’s devotion to health and fitness since he arrived on these shores. But it looked as if a few of his charges had been ignoring his dietary advice as they puffed and wheezed their way through a one-sided match.

Craig Gordon has been heavily criticised by fans for the two goals which Celtic conceded over in Sweden. But the goalkeeper, so often his side’s saviour in Europe last season, kept the scoreline down with some exceptional blocks, not least from Nikola Djurdjic just before half-time.

The zonal marking which the Celtic manager is an advocate of appeared to be responsible for the first goal. The Malmo captain and striker Markus Rosenberg was allowed to breeze into the six yard box, get on the end of a Yoshimar Otun corner and net completely unchallenged. It was one of three goals the Scottish champions conceded at corners in the two games.

Serious questions have to be asked of Deila tactically in the wake of this double header. His side dominated the opening half hour of the first leg last week, forged two goals in front and could have killed off the visitors before half-time if they had taken their chances. Letting Age Hareide’s team back into the tie exposed a terrible naivety at European level.

Stefan Johansen set up the opening two goals in that outing and Deila probably persevered with his underperforming countryman in the rematch in the hope that he could carve out an opening with another defence-splitting pass or penetrating delivery into the box.

Johansen, though, was utterly anonymous and should really have been substituted at half-time and replaced with the vastly experienced Kris Commons. Instead, Stuart Armstrong, who had been bright on the left flank in the opening 45 minutes, came off.

You could understand Deila’s decision to prefer Charlie Mulgrew to Emilio Izaguirre at left back given the Honduran internationalist’s propensity for getting caught out of position. But it, too, is not an experiment which he should repeat.

So where now for Ronny Deila and Celtic? They will, despite the fine starts made by both Aberdeen and Hearts in the Ladbrokes Premiership this term, retain their title by a comfortable margin and should challenge strongly for the League Cup and Scottish Cup.

The continued absence of Rangers from the top flight means that no other domestic rival has Celtic’s vast resources at their disposal and is capable of launching a serious challenge to their supremacy in Scotland.

Europe, though, is a far sterner test and it is one that Deila has not passed. Overcoming Malmo was about as straightforward an assignment as Celtic could have hoped to have been handed at the play-off stage and they failed to negotiate it.

It is in the Europa League where the true test will come for Deila. If his side struggles again on the continent then supporters who have grown used to memorable European nights at Parkhead may decide he is not the man to drive the club forward and could turn against him.

The defeat to Malmo will cost Celtic in the region of £13 million this season. They would have collected over £20 million for progressing to the Champions League group stages before they had even won or drawn a game. Participation in the Europa League is only worth around £8 million.

But just how would Celtic have fared in Europe’s premier club competition if they had got through? On the evidence of Tuesday night, not very well. There is no guarantee they will fare much better in the tournament they are in given the calibre of club involved. Schalke, Napoli, Spurs, Villareal, Marseille and Liverpool will all be in the draw in Monaco tomorrow afternoon.

Most Celtic fans have taken Ronny Deila to their hearts since he was appointed. But many remain to be convinced. He will have to prove his worth to them after this huge setback.

Otherwise, the Ronny Roar will be no more.