He made his debut in the Italian top division the following season, and his performances throughout the year earned him a transfer to Napoli in 2015.

Following a successful first season in Serie A with Empoli, he also earned his first international call-up in 2015, making his Italy debut the same year.

A former member of the club's youth system, his debut for the Cesena senior side came on 14 May 2005, in a 3–3 away from home draw with Genoa, during the 2004–05 Serie B season.

[4][5] The 2009–10 Serie B season was similarly strong for Valdifiori, who made 36 appearances and even managed his first professional goal - the 2nd in a 2–0 win over his former side Cesena.

After having a very successful first season in the Italian top flight with Empoli, which saw him earn his first call up for the Italy national team by manager Antonio Conte, Valdifiori officially joined Napoli on 20 June 2015[6] for a reported fee of €5.5 million, where he was reunited with his former Empoli coach Maurizio Sarri, also becoming the manager's very first signing at the new club.

[12] In March 2015, Valdifiori was called up by coach Antonio Conte to the Italy squad for the first time, for a Euro 2016 qualifier against Bulgaria, and a friendly against England.

[13] On 31 March 2015 he made his debut in the latter match against England, starting the 1–1 draw at the Juventus Stadium in Turin, and making way for Marco Verratti after 67 minutes.

[14] A creative, right-footed central midfielder with good vision, Valdifiori's preferred role is as a deep-lying playmaker in front of the defence, where he is able to utilise his passing ability to set the tempo of his team's play, and create scoring opportunities for team-mates.