Barcelona will wear their Senyera kit at home for the first time in the history of the club. The kit features the colors of the Catalonia flag.
Gerard Piqué joined a march for Catalan independence on Thursday.
The club, however, have attempted to distance themselves from suggestions that the kit change marks support for the movement, stating: “The Senyera shirt is not being worn because of the 11 September [National Day] – we are doing it to commemorate the 300th anniversary of the fall of Barcelona at the hands of the troops of Philip V and the French in 1714.”
Athletic Club will also wear their 'nationalist' kit for the match.