Rui Patricio and Daniel Podence were the first two players to request their deals be cancelled, while manager Jorge Jesus has left for Al-Hilal in Saudi Arabia.
Following the exit of Rui Patricio, as well as head coach Jorge Jesus, the foursome of Dost, Carvalho, Martins and Fernandes chose to go public on Monday, and filed notice with the Portuguese Securities Market Commission that they meant to terminate their contracts, invoking "just cause" after being attacked in their workplace.
The move comes several weeks after a group of fans attacked several players at the club's training ground last month after Sporting failed to qualify for next season's Champions League. Police detained more than 20 suspects in the hours following the incident.
De Carvalho had rejected calls by senior club members to stand down, accusing his critics of blackmail and "a concerted attack on Sporting".
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De Carvalho threatened to suspend 19 players after Sporting's 2-0 loss to Atletico Madrid in the Europa League in April, in a freakish Facebook post singling out some of the club's key names.
William Carvalho, Gelson Martins, Bruno Fernandes have all made a decision to break their club contracts with Sporting Lisbon following a season of off-the-field trouble between players, fans and the owner.
He has also refused to accept the legitimacy of a vote later this month to depose him.
According to claims from Portuguese news outlet O Jogo, Fernandes has submitted his resignation from Sporting, requesting that his contract is rescinded.