CELTIC's position on the Sion case can be summed up like this: they know what should happen, but they don't know what will.

Two days after being baffled and confused by one decision which went against them -- a verdict of “not proven” being returned on the Hearts fan accused of assaulting Neil Lennon for sectarian reasons -- they will be at the mercy of another decision-making body this afternoon.

Celtic aren’t in the dock for Uefa’s control and disciplinary body but the repercussions for their season are massive depending on what the governing body decides to do with Sion.

If the decision goes one way Celtic will be resurrected in the Europa League. Instead of a season of only domestic fare they will face matches against Atletico Madrid, Udinese and Rennes, ties which could collectively earn them close to £5m from Uefa money, television income and gate receipts.

It would not be an insubstantial sum, some or all of which could be put Neil Lennon’s way in the January transfer widow. That could fund the signing or two which might win them the league.

And if the decision goes the other way? They would be baffled and confused again. No resurrection, no European ties, no money . . . and, as far as they are concerned, no justice.

Celtic cannot claim to deserve a place in the Europa League on football terms -- they were beaten fair and square by a superior Sion side -- but the Swiss have an interpretation of a Fifa signing ban which completely contradicts what Fifa, Uefa (and predictably Celtic) believe to be the case. As far as Fifa are concerned, they broke the rules.

Celtic played both legs of their play-off defeat under protest, insisting that Sion had breached a transfer embargo. That was imposed by Fifa after illegality in their signing of Egypt goalkeeper Essam El-Hadary three years ago.

The ban covered two transfer windows, which would appear to include the one which closed this week. Sion signed five players this summer. One of them, Pascal Feindouno, scored twice in Celtic’s 3-1 second-leg defeat.

Sion had challenged the terms of the ban in the Swiss civil court and won their case, securing a ruling that the embargo had ended. That prompted the Swiss FA to give them approval to play the “ineligible” players in domestic matches.

But Gianni Infantino, Uefa’s general secretary, has said the civil court has no jurisdiction over European football competitions and confirmed that Sion could be expelled from the Europa League. He did, however, acknowledge there was a dispute over whether a two transfer-window ban meant two transfer windows or parts of several transfer windows.

Celtic also received encouragement when Michael Platini, the Uefa president, said Sion had not respected the transfer ban. The Scottish Football Association have also supported the Parkhead club’s protest.

Peter Lawwell, Celtic’s chief executive, sat alongside the former Prime Minister, Gordon Brown, in the SFA’s Hall of Fame at Hampden yesterday as Brown was confirmed as the patron of the John Thomson Memorial Committee.

Thomson was the legendary Celtic goalkeeper who died in an accidental collision during an Old Firm game in 1931. He was a Fifer, like Brown, and is the subject of “The Prince -- The Johnny Thomson Story”, a play which opens at the King’s Theatre in Glasgow on Monday.

Centre stage for Lawwell today, though, is the Sion case. He was at pains to show respect to Uefa’s decision-makers, but admitted he was in the dark about what ruling they would reach. “You never ever know. I think Michel Platini speaking out was at an informal briefing that will have no bearing on the facts or the outcome.

“You never know. I think we have a strong case, we have presented a strong case, but you never know. We have to respect those who are making the judgment. We don’t have any indications about what will happen. We have to respect the Uefa processes so it’s difficult to comment. My understanding is that, if they are found guilty of fielding ineligible players, the tie is forfeited. That is my understanding of the rules and that is our expectation, if they find in our favour. If somebody breaks the rules, they should pay the price.”

Because Sion and their outspoken president, Christian Constantin, have openly challenged Fifa in the courts, Lawwell said it had become an enormously significant case for football in general. “This could be a landmark case for football. What you have here is the rules and regulations of football being challenged by a domestic court in Switzerland, the law of the land. Clearly there are a number of huge issues that could throw up, not just with the registration of players but the specific nature of football and its regulations. It’s a huge issue for Fifa. A huge issue. But I wouldn’t say the credibility of UEFA and FIFA is at stake, not at all. These guys know what they’re doing. We respect the process. There’s a process in place and hopefully the judgment goes our way.”

Constantin said yesterday that he understood Celtic’s motivation for lodging a protest, but he was confident Sion would prevail. “The bottom line is that we are in the right. There’s no doubt,” he said. “It’s just that there are cases where Fifa want to take unilateral decisions by force rather than by just means. Uefa approved the list of players we submitted, but now, because of pressure from Fifa, they’re trying to find justification for making us forfeit the tie. Fifa may try to mask the facts, but that won’t be easy.”

He said Sion would appeal to Uefa and a civil court, rather than the Court of Arbitration for Sport, if today’s decision goes in Celtic’s favour. “The civil court has already said we’re right, so if the follows the same line, he’ll find in our favour again.” Constantin even claimed a judge could block the start of the group stage if there was no resolution before it is due to begin on September 15.