Inter Milan defender Francesco Acerbi lost his cool after a Club World Cup fan wearing a Paris Saint-Germain shirt in Seattle taunted him about last month's Champions League final, with the Italian threatening to beat him up if the teasing continued. The fan brought up a humiliating moment from Inter's 5-0 defeat by the French champions in Munich, in which Acerbi was left sprawling after some dazzling footwork by Bradley Barcola. Inter Milan defender Francesco Acerbi had a night to forget in the Champions League final. The translator told the fan in English on Thursday: "You must be serious with him." Seconds later, Acerbi stepped in to say in Italian: "I'm serious.