[3][4][5] He made his Serie A debut for the club on 14 March 2010 in a league match against Parma, coming on as a 79th-minute substitute for Simone Tiribocchi.

On 9 July 2010, Gabbiadini joined Serie B side Cittadella, along with Daniele Gasparetto, in co-ownership deal for a peppercorn of €500,[7] as part of the negotiation that saw Atalanta sign Matteo Ardemagni.

On 21 June 2011, Gabbiadini returned to Atalanta after his co-ownership deal was resolved for €1.5 million for 50 percent of his registration rights.

He made 25 league appearances for the club, including eight starts, and scored his first Serie A goal on 25 March 2012 in the 2–0 home victory over Bologna.

In January 2015, Gabbiadini joined Napoli for a reported fee of €13 million, to be split equally between Sampdoria and Juventus, each owning 50 percent of the player at the time of the deal.

[17] He made his debut on 11 January against former team Juventus at the Stadio San Paolo, replacing José Callejón for the last 17 minutes of a 3–1 defeat.

[34] On 15 August 2012, Gabbiadini made his debut with the Italian senior team, playing in the second half of the friendly match against England in Bern, which Italy lost 2–1.

[34] On 17 November 2015, he came off the bench to score his first international goal for Italy in the 66th minute of a 2–2 friendly home draw against Romania, in Bologna, although he was forced off early after sustaining an injury.

[36][37][38][39][40] His preferred role is on the right, however, where he is capable of cutting into the middle and curling shots on goal with his stronger left foot, rather than looking to deliver crosses into the area from the touchline.

[47] Gabbiadini's older sister Melania is also a forward, who has spent most of her career with AGSM Verona and plays internationally for the Italy women's national football team.

[49] On 17 June 2017, Gabbiadini married his long-term partner Martina Rubini in the parish church of Sasso Marconi, Bologna.