On 10 August 2013, Hamšík signed a contract extension with Napoli, tying him to the club until the summer of 2018. In the first match of the 2013–14 Serie A season on 26 August 2013, Hamšík scored Napoli's second and third goals in the club's 3–0 home defeat of Bologna. Hamšík continued his scoring form in Napoli's following match, netting another brace in their 4–2 away victory over Chievo on 31 August.