Former Sporting Clube de Portugal president Bruno de Carvalho is accused of being the mastermind behind the attack and was charged with 44 crimes of kidnapping -- which is termed as "terrorism" under Portuguese law -- aggravated threat, violent assault, possession of forbidden firearms and breaking and entering.
Judge Carlos Delca decided to go ahead with the trial saying none of the defendants brought forward any evidence "capable of shaking the foundations of the accusation," court documents seen by CNN show.
Social media criticism
The defendants were charged after a group of around 50 fans attacked Sporting CP players and staff in May 2018, at the club's training ground, after the team failed to qualify for the UEFA Champions League. Seven of the team's players later terminated their contracts with the club.
Four of them -- Rui Patricio, William Carvalho, Gelson Martins, and Bruno Fernandes -- were part of Portugal's 2018 World Cup squad.
The training ground incident followed repeated public criticism by then president Carvalho who became famous for using social media to criticize the squad.
In April 2018, he claimed to have suspended 19 first-team players after a Europa League defeat by Atletico Madrid, although he deleted the post on social media and most of the players featured in their next game.
Carvalho, who has since been voted out of office by club members, reacted to the court decision on Facebook writing "those who purposefully allow someone to be continuously roused, slandered, and defamed is a criminal ... and a coward!"
The former Sporting president will await trial in freedom along with four other defendants who have to present themselves at a local police precinct every two weeks.
One of the remaining defendants, Nuno Mendes, the leader of the supporter group known locally as "Mustafa," has been remanded in jail due to an additional charge of drug trafficking.
The other defendants will await trial under house arrest.