Sulley Muntari walked off the pitch towards the end of Pescara's 1-0 loss to Cagliari on Sunday after being booked by the referee who ignored his calls to halt the game for alleged racial abuse.
The 32-year-old former Ghana international star, who has previously played for Udinese, Portsmouth, Inter and Milan, had asked Daniele Minelli to stop the match in the 89th minute.
He was, however, booked instead for dissent, before leaving the field where he confronted the Cagliari fans.
Facing the stands, he shouted: "This is my colour."
Pescara boss Zdenek Zeman explained: "He asked the referee to intervene, but he [said he had] neither heard nor seen anything.
"Muntari was right, but he shouldn't have left the pitch."
Muntari played 84 times for his national team and in three World Cups from 2006 to 2014.