Pato recently returned to Milan’s first team following an injury lay-off and scored his first goal of the season in a 1-1 Champions League draw at home to Malaga yesterday.
But his penalty miss the Fiorentina defeat at the San Siro on Sunday was seen by some fans as a costly mistake.
According to Corriere dello Sport newspaper a group of angry Milan fans waiting for Pato to leave the stadium surrounded and banged on his car and launched verbal threats at the Brazilian.
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