Celtic face a further wait over their Europa League fate as Sion fight their expulsion from the competition on several fronts.
The Swiss club have vowed to challenge their removal, for fielding ineligible players, in their country's civil courts while appealing directly to UEFA. The Hoops were reinstated in the tournament on Friday after protesting over Sion's decision to field the players, including midfielder Pascal Feindouno, who scored two goals as Sion won 3-1 following a goalless first leg.
A statement from Sion read: "FC Sion received 12 pages of confused explanations (in French) for the acceptance of the protest. The decision comes from the three UEFA judges who decided to keep Celtic in the competition. For us, it's a pure revenge against our president."
Celtic are due to face Atletico Madrid in Spain next Thursday but Sion are determined to overturn the decision. UEFA have yet to confirm an appeal has been received but the deadline is not until Thursday night.
The statement added: "FC Sion officially appealed to UEFA on Monday, in order to obtain the cancellation of the protest. We remind that Celtic received before its home game an official document from the European federation: it mentioned that players were officially eligible. Sion prepares its travel to Madrid.
"Players (individually) and the club are now bringing legal actions against UEFA at Swiss civil court. Civil court already gave the players the right to play (before the games), that was not respected by the UEFA. This is a serious violation of Swiss laws and may result in penal proceedings."
Sion were handed a transfer embargo for breaching rules over the signing of Egypt goalkeeper Essam El-Hadary three years ago but the club and FIFA have different interpretations over the length of the ban.
Sion have already won a civil court ruling over the issue, which prompted their domestic football authorities to allow them to field the five affected players. And the club are adamant UEFA gave them the green light to play them.
They believe the crucial document is a letter sent by UEFA general secretary Gianni Infantino to Celtic and the Scottish Football Association prior to the first leg, which read: "The Swiss Football Association has confirmed to us that the players are qualified under their regulations. Therefore, UEFA has to consider that these players are eligible to participate in the UEFA Europa League."
However, the letter goes on to state that the players could later be deemed ineligible and that Celtic had the right to lodge a protest.
Copyright (c) PA Sport 2009, All Rights Reserved.