The striker blew his top on Twitter after he was sent off for two bookings in three minutes during Friday night's 0-0 World Cup qualifier in the Czech Republic.
"Good morning," he wrote on his Twitter account @FinallyMario.
"Yesterday my reaction was not right, I apologise... SORRY... To my team... I need to learn... still."
He had also taken to Twitter last night and raged against the abuse he was receiving via the social network.
"Write what you want, but at the Confederations Cup you can support another country and I tell you that from the HEART," he wrote.
"Also, go back and watch the game carefully, ALL OF IT."
He also replied to specific users with messages such as: "I know full well what humility is, as my parents taught me good manners and respect, but you don't know me at all."
"I am Italian and I want respect for my national team, but I am not Superman. Therefore have some respect for me."