Early career Born in
Policoro in the
Province of Matera, Zaza grew up in
Metaponto and began his youth career with Stella Azzurra from
Bernalda in 1997. He remained with the organization until 2002, when he moved to the youth academy of Valdera at the age of 11. He remained until 2006, when he was scouted by
Serie A side
Atalanta, whom he joined shortly after. He remained within the club's youth team for four years and even began to earn senior call-ups towards the end of the
2008–09 Serie A campaign. He made his Serie A debut on 1 March 2009 in a 0–2 home defeat to
Chievo Verona as an 86th-minute
substitute for
Ferreira Pinto. He made two further substitute appearances for Atalanta that season, though he remained within the club's youth setup for the entire
2009–10 Serie A campaign.
Sampdoria In July 2010, Zaza transferred from Atalanta to fellow Serie A side
Sampdoria on a four-year contract. With the Genoa-based club, he was enlisted in the club's
Primavera (under-20) youth team for the 2010–11 season, though he also earned several first team callups, including two substitute appearances against
Genoa and
Fiorentina during the
2010–11 Serie A campaign. He was promoted to the first team at the conclusion of that season.
Juve Stabia and Viareggio (loans) On 14 July 2011, Zaza was officially sent out on loan to
Juve Stabia in Serie B on what was set to be a season-long deal. After just four appearances and no goals for the club, Sampdoria opted to recall the player during the 2012 January transfer window. On 7 January 2012, the club loaned the player to
Lega Pro Prima Divisione side,
Viareggio on a six-month deal to provide the youngster with regular first team experience. His stint with the third-division club turned out to be very successful; he managed 11 goals in 18 league appearances, 17 as a starter.
Ascoli (loan) After returning to Sampdoria on 30 June 2012, Zaza joined
Ascoli on another season-long loan deal ahead of the
2012–13 Serie B campaign. He officially joined the club on 16 July and made his debut in a 1–3 home loss to
Bari on 1 September. Zaza went on to score 18 league goals in 35 Serie B appearances (30 as a starter) en route to becoming the sixth top goalscorer for the season. His goals were unable to prevent Ascoli's relegation as they finished the season 20th in the league table. He returned to Sampdoria on 30 June 2013.
Sassuolo On 9 July 2013, Juventus purchased him outright from Sampdoria for €3.5 million. Simultaneously, he transferred to Sassuolo from Juventus in a
co-ownership deal for €2.5 million. He returned to play in Serie A in the first round of the
league, with Sassuolo losing to Torino 2–0. On 1 September 2013, during the second round of the league, he scored his first goal in Serie A as the team lost 4–1 to
Livorno. Thanks to his effort, Sassuolo secured their first point in the Italian top flight, with the goal scored in the fifth day against
Napoli, 1–1. On 20 June 2014, Sassuolo bought Zaza outright from Juventus for another €7.5 million. Juventus, however, retained the right to re-purchase Zaza for a reported €15 million by 30 June 2015 and €18 million by 30 June 2016.
Juventus On 7 July 2015, Juventus announced that they had exercised their option to sign Zaza for €18 million from Sassuolo. It was reported that the return of
Domenico Berardi to Sassuolo for a €10 million fee was part of the deal. On 23 September 2015, Zaza opened the scoring in the 50th minute on his debut, a 1–1 draw against
Frosinone. On 30 September 2015, he scored the final goal against
Sevilla in the
UEFA Champions League group stage to secure a 2–0 win; this was his first Champions League goal. He scored the opening two goals of a 4–0 win over
cross-city rivals Torino in the
Coppa Italia on 16 December.
West Ham United (loan) On 28 August 2016,
West Ham United announced that they had loaned Zaza for a €5 million loan fee, with a €20 million permanent obligation to buy after a certain number of Premier League appearances, plus €3 million in bonuses. He made his debut with the club on 10 September, in a 4–2 home defeat to
Watford in the
Premier League. Zaza made 11 appearances for West Ham, eight in the Premier League and three in the
EFL Cup, all without scoring. His last game came on 30 November, in a 1–4 away defeat to
Manchester United in the EFL Cup. He developed a knee injury in December and was not selected again before leaving the club in January 2017. for a €2 million fee, with a €16 million permanent obligation to buy fee after a certain number of first team appearances by 30 June 2017, plus €2 million in bonuses. On 21 January, he made his debut with the club in a 2–0 away win against
Villarreal. On 19 February, he scored his first goal for the club in a 2–0 home win over
Athletic Bilbao. In his next league appearance on 22 February, he scored the opening goal with a notable left footed strike on the turn to help Valencia to a 2–1 home victory over
Real Madrid. On 10 April, Zaza was bought outright by Valencia from Juventus until 2021 for the previous agreed fee, effective after 30 June. On 19 September, he scored a
hat-trick in under 10 minutes of a 5–0 home win over
Málaga.
Torino On 17 August 2018, he was loaned to
Torino for €2 million, with a €12 million obligation to buy at the end of the season. In the first game of new manager
Davide Nicola, he scored two second-half goals to help Torino draw 2–2, having been two goals down at half-time. On 31 August 2022, Zaza's contract with Torino was terminated by mutual consent. ==International career==