AEK Athens was condemned to relegation after Greek league officials deducted three points for violence by club fans at a match last weekend.
A disciplinary board on Friday also ruled that last Sunday's match would be awarded 3-0 to relegation rival Panthrakikos.
AEK fans stormed the pitch after it fell behind 1-0, and the game was stopped in the 88th minute.
The team was also docked two points to start next season, and fined ?7,000 ($9,100) for the fans' use of flares and firecrackers.
AEK described the sanctions as a ''premeditated crime'' and said it would appeal next week.
One of Greece's three largest clubs, AEK is on the brink of financial collapse - the latest high-profile casualty in the crisis-hit country - following multiple recent indictments of current and former club officials for allegedly violating the terms of a tax settlement with the state.
The three-member disciplinary panel issued its penalties after a 12-hour meeting, rejecting a legal motion from AEK that maintained the match at Athens' Olympic Stadium was stopped without following the correct procedure.
''The match was stopped in the 88th minute after fans of the host team entered the pitch in large numbers, prompting players from both teams and match officials to rush to the dressing rooms,'' the panel said in a written statement.
The penalties drew an angry response from the club, who called them a product of Greece's ''corrupt system.''
''The disciplinary body has decided to deprive us of the right to fight for our salvation. But AEK never gives up because we have learned to fight on the playing field until the end,'' the club said. ''We know the fans of our team will never forget this.''
The points penalty confirmed AEK will finish second-to-last in the 16-team standings, with both bottom clubs relegated.
AEK has fallen to 27 points, and Panthrakikos improved to 33 and safe from the drop with one round left this weekend.
AEK fans remain bitter at league organizers for awarding the championship to Olympiakos in 2008 despite AEK finishing the season on top of the standings. Olympiakos was later awarded a match it lost that year because its rival violated transfer procedures.
On Thursday, about 200 AEK fans gathered outside the disciplinary hearing which was heavily guarded by riot police.
Caretaker coach Trianos Dellas, a key member of Greece's winning 2004 European championship squad, said before the decision was announced that he asked the league to show the team ''fair treatment.''
''What I asked from the committee was for just treatment,'' he said. ''Matches should end inside the football ground, not in court.''
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AP Television's Srdjan Nedeljkovic and Raphael Kominis contributed.
