Before the win, Sevilla announced the board would not be attending the game in protest against Barca's Negreira case investigation.
In response, Barca announced: "FC Barcelona wishes to show publicly its condemnation of Sevilla FC's unjustified and inappropriate attack after the club today refused to attend the institutional lunch amongst directors prior to today's game between the two teams the Estadi Olímpic Lluís Companys, where its representatives have also refused to take their places in the directors' box.
"Furthermore, the Andalusian club has published a statement in which it shows its 'indignation and condemnation for the practices carried out by former FC Barcelona directors named in the Negreira case' and announces its absence from the directors' box for today's game.
"FC Barcelona believe this to be an attack against the Catalan institution and an unacceptable offence.
"The aforementioned Negreira Case cannot be used as an excuse for such measures, given that the legal case is in a very early phase and the position of Sevilla FC clearly prejudices the facts that have yet to be established in any shape or form.
"Moreover, the legal decision announced today does not alter in any way the legal and factual position of FC Barcelona in the process; it is legal disputable; it does not come from any firm basis and it will be appealed against by the Club.
"Furthermore, the FC Barcelona president, Joan Laporta, appeared in an extraordinary assembly of LaLiga, called for this very case, where he gave comprehensive clarifications and explanations on this question.
"Sevilla FC's position, therefore, appears illogical given that on the one hand it ignores the presumption of innocence and on the other denies FC Barcelona its right to a defence in the legal process which is currently ongoing.
"In the light of this unacceptable and unjustifiable position of Sevilla FC, FC Barcelona believes that all institutional relations with the institution from Seville have been broken off until their current position is rectified."