The 25-year-old Slovakian had the windows of his car smashed by two armed assailants, and was forced into giving up his Rolex watch, but escaped unharmed.
"I'm really unhappy about what happened after the match. It's the third time that it's happened to me since I've been here," Hamsik told his club's official website. "I'm really sorry that these kind of things happen but unfortunately it is one of the hardships of living in Napoli."
Other Napoli players such as Edinson Cavani, Valon Behrami and Ezequiel Lavezzi have all fallen victim to crime in the city in recent years.