Corinthians fined star forward Jo for wearing green boots, the colour of their arch Brazilian rivals Palmeiras.
Former Manchester City forward Jo sparked backlash after wearing light green boots in Sunday's goalless draw away to Bahia in the Campeonato Brasileiro Serie A.
After Corinthians fans were left outraged, the club sanctioned and warned the former Brazil international, who is prohibited from wearing the boots again, even in training.
"Sport Club Corinthians Paulista's football board communicates that they spoke with striker Jo about the use of football boots in the match against Bahia, this Sunday," a statement read.
"The player was warned, fined and will not wear them again, neither in training or in games."
Jo, who emerged from Corinthians' youth team in 2003 before going on to play for the likes of CSKA Moscow, Everton and Galatasaray, issued an apology.
"I would never use green boots because of my history with Corinthians, a club I have loved since I was little," the 34-year-old said in a statement via Veja.
"I would never disrespect Corinthians, much less the fans. I have always honoured this shirt and I always will honour it."
Corinthians and Palmeiras share one of the fiercest and oldest rivalries in Brazilian football – the Paulista derby.
The Paulista derby is ranked among the 10 greatest derbies in world football.
Palmeiras are fourth in the Campeonato Brasileiro Serie A through five games this season, five points better off than 11th-placed Corinthians.
Corinthians last won the Campeonato Brasileiro Serie A in 2017, while Palmeiras – winners in 2018 – conquered the Copa Libertadores last year.