It's an image in the mind's eye that's hard to shift.

Stephen Robinson studying Wilfried Nancy's Celtic as the hours tick by to Sunday's Premier Sports Cup final. Forensic analysis in every waking hour. And for the St Mirren manager, suddenly, hope.

A little over a week ago, as Martin O'Neill, the great redeemer, exited the club in a fanfare of gratitude and optimism, Robinson would have to face a team content in its own skin again.

What he must see now is something altogether different.

He's got to be seeing weakness and a chance. Everybody else can see it.

Nancy had two ways to go when he took over - he could have done a steering job with O'Neill's team until the January transfer window, when he could start putting his own imprint on things.

Or he could dive right in. And dive right in he has done.

On the back of losing to Heart of Midlothian on Sunday in his first game in charge, Nancy's side have lost a second game, a 3-0 doing by Roma at a fast-emptying and, at the end, booing Celtic Park.

It's not so much that they lost to Roma - O'Neill, Brendan Rodgers and Ange Postecoglou could all have lost to the Italians just as easily - but it's the confusion that exists under Nancy now that's intriguing, the speed with which O'Neill's work has seemingly unravelled.

The players pressed into ill-fitting roles. The apparent devotion to an ideology of how this team must play regardless of whether the players he has inherited are cut out to play it.

The fact that Nancy is now the first Celtic manager in history to lose his first two games. The reality that Thursday was only the second time in history that Celtic conceded three first-half goals at home in Europe.

The uneasy truth that Liam Scales' own goal was the earliest concession in a European game at Celtic in more than a decade.

These are not the kind of records that Nancy came here to set. The brutal realities of life as a Celtic manager have descended on his head in double-quick time.

The crumbs of comfort wouldn't feed a sparrow right now. They amount to Celtic not having caved in and conceded more goals in the second half against Roma. Nancy did his best to feast on that in the aftermath.

Has psychological damage been done this past week? You argue that it has. Do Celtic look confused on the pitch? Yes, again. Will Nancy go back to basics on Sunday? Unlikely. Are Celtic fans more worried now about the League Cup final than they were a little over a week ago? In the case of some or many, undoubtedly.

Nancy was subjected to an awful lot of garbage in the wake of Tynecastle, as if his tactics board was an affront to football, as if his perfectly normal trainers made him any less capable of doing his job.

The one truth about managing Celtic, or any other team with high demands, is that, if you are a winning manager, you can turn up in a tutu. Nobody would care. If anything, it would spark a trend - if you're winning.

Now that he's off to a losing start, the doubt is out there, the feeling that maybe Celtic should have stuck with O'Neill for a while longer or that, perhaps, it was a bit reckless to give control of the team to a manager with little experience and no exposure to the kind of suffocating heat of a Glasgow giant.

Again, it's not just the losses that might be making some Celtic fans gulp. It's the rapid reimagining of O'Neill's team and the disintegration of the organisation that had been created.

We can make too much of what O'Neill achieved - his side weren't always easy on the eye in his brief second spell - but they won all bar one game. They toiled badly at times, but they got the job done, they triumphed on the road in Europe, which is something Celtic rarely do.

Nancy has gone to three at the back, and with three left-footers, which is something that Derek McInnes gorged on at Tynecastle. He has tried to reinvent a left winger, Yang Hyun-Jun, into a right wing-back - and it hasn't worked. He's tried to recast Sebastian Tounekti, a left winger, into a left wing-back. That hasn't worked either.

Nancy doesn't seem to think that these changes are a big deal, but the demeanour of his team suggests otherwise. Against Roma, and at times against Hearts, they looked like a ship that's been taken off course due to choppy waters.

His players look confused in a system that doesn't agree with them. It's only two games and it's a tiny sample size. In a normal world. Glasgow is not a normal world.

Judgement Day can come in the space of 45 minutes in this place. In the case of Russell Martin, the former Rangers head coach, it came before a whistle was blown in a competitive match for a section of the support. Things are different in this city.

Nancy had precious little time on the training ground with his players, but he still made gung-ho changes against Hearts when a steadier approach might have been wise.

Maybe if John Kennedy was still in the coaching team then he might have been persuaded to go more gently and more slowly, but Kennedy, a near-30-year veteran of the club as player and assistant coach, left when Rodgers went. Some clever counsel may have left with him.

The concern for Celtic folk is that Nancy gives the impression of a man wedded to a system of playing rather than adapting his system based on what he has in the dressing room. Square pegs don't tend to fit into round holes, no matter how hard you try to hammer them in.

Comparisons have been made to Postecoglou, but this is not the same thing. Yes, Postecoglou had a "my way or the highway" approach, but he had walked into a losing club in desperate need of a rebuild.

Nancy needs new blood, but he doesn't need to perform the major surgery that Postecoglou needed to perform. He doesn't need to rip it up and start again as the Australian had to do.

Nancy deserves time, deserves a January window, deserves some new players of his own choosing. You only get those things in the future if you win in the here and now. That was something that Martin, at Rangers, claimed he knew, but did he really? His medium to long-term "no gain without pain" mantra suggested otherwise.

It's a case study that Nancy, even this early, could do with looking at. It's unlikely that he will switch back to a more pragmatic O'Neillesque formation on Sunday, when St Mirren will attempt to make it a battle and expose the uncertainty in the Celtic team.

This might all come right. If Callum McGregor lifts the trophy at Hampden then everything becomes easier - for a day or two. It would give Nancy a lift, it would give him credibility and a chance to bond with supporters. He needs that trophy, big-time.

The flip-side, the mission that Robinson is working on, is not something the Frenchman wants to contemplate. A third defeat and he will feel like the sky has fallen.