Ogbonna began his early career in the youth set-up ofCassino, where he played as acentral back. In 2002, he was noticed by Torino, which, on the recommendation ofAntonio Comi,[3] bought him for €3,000 and assigned him to their youth team.[4] In the 2006–07 season he was regularly called up to the first team and on 11 February 2007 he made his debut inSerie A at age 18, againstReggina (1–2), as a starter under coachAlberto Zaccheroni.[5] At the end of season he totalled 4 league appearances.
The following August he moved on loan toCrotone inSerie C1,[6] making 22 league appearances in the league and nearly earning promotion toSerie B, losing in the semi-final play-offs.
In the2008–09 Serie A season he returned to Torino, collecting 19 league appearances and four inCoppa Italia. Torino, however, were relegated toSerie B at the end of the season. Starting from 2009, after the relegation of the club to Serie B, he earned his place as a starter for theGranata. On 17 April 2010, Ogbonna scored his first goal for Torino in the match againstCesena, finishing 1–1.[7] On 15 August 2010, in the second round ofCoppa Italia againstCosenza (won 3–1 in extra time), he wore thecaptain's armband for the first time. In three Serie B seasons with Torino, Ogbonna made 105 appearances, helping the club return to Serie A after finishing second toPescara during the2011–12 season.
On 2 February 2012, he renewed his contract with Torino until 30 June 2016.[8]
On 11 July 2013, Ogbonna underwent a medical atTurin's Fornaca, Isokinetic and the Istituto di Medicina dello Sport ahead of his proposed cross-town move toJuventus.[9] After passing the medical, he officially signed for Juventus for a transfer fee of €13 million, with an additional €2 million to be paid in future bonuses.[10] He became the first player to becomecaptain of theGranata and transfer to rivals Juventus,[11] sparking much dislike with his old supporters of Torino.[12]
He made his Champions League debut in on 17 September 2013, againstF.C. Copenhagen.[13] In his first season, despite being behindAndrea Barzagli,Leonardo Bonucci andGiorgio Chiellini in the pecking order at centre back, Ogbonna managed 25 appearances in all competitions, mostly starting in matches in the latter half of the season as the team was heavily rotated for league, Coppa Italia and Champions League matches. Ogbonna played 16 league games for Juventus in the2013–14 season, as they won Serie A title.[13] He was also a member of the side which won the2013 Supercoppa Italiana[13] In the2014–15 season, Juventus defended the Serie A title once again, with Ogbonna making 25 league appearances, and the2014–15 Coppa Italia.[13] On 6 June 2015, he was an unused substitute as Juventus lost theChampions League Final 3–1 toBarcelona in Berlin.[13]
On 10 July 2015, Ogbonna joinedPremier League clubWest Ham United, on a four-year contract, for €11 million to be spread over the next three financial years.[14][15] He made his debut 20 days later in the Europa Leaguethird qualifying round, starting againstAstra Giurgiu; in the 82nd minute he netted anown goal equaliser as West Ham drew 2–2 at theBoleyn Ground.[16] On 9 February 2016, Ogbonna scored his first goal for the club, netting an injury-time match-winning header in the 121st minute of a 2–1 home win overLiverpool, in the fourth roundFA Cup replay.[17] Having played 18 of a possible 22 Premier League games for West Ham in the2016–17 season, he was ruled out for the remainder of the season as he required an operation. West Ham manager,Slaven Bilić, said that Ogbonna had played every game of the season despite carrying the injury.[18] He returned for the final game of the 2016–17 season, a 2–1 away win againstBurnley.[19] In June 2017, Ogbonna signed a new contract with West Ham committing him to the club until 2022.[20]
In June 2024, West Ham announced that Ogbonna, alongside teammateJoseph Anang, would be leaving the club at the end of the2023–24 season; he made 249 appearances for theHammers, scoring 13 goals.[25][26][27] Having played 201 Premier League games, he was the second Italian footballer with the highest number of appearances in the league at the time of his departure, behind onlyGianfranco Zola.[28][29]
On 27 August 2024, Ogbonna signed forEFL Championship clubWatford as a free agent, on an initial season-long contract.[30]
On May 2025, it was announced that he would be released by Watford at the end of the2024–25 season, having played inconsistently during his time with the club.[31]
Ogbonna made hissenior debut on 11 November 2011 in a 2–0friendly victory againstPoland, where he came on as a substitute forDomenico Criscito in the 77th minute.[32]
Ogbonna was included by managerCesare Prandelli in the Italian 23-man final squad forEuro 2012, but did not play during the competition.[32]
In May 2016, Ogbonna was included in the provisional 30-man Italy squad forEuro 2016;[33] On 31 May 2016, he was named inAntonio Conte's final 23-man squad for the tournament.[34] Ogbonna made his only appearance of the tournament on 22 June, in Italy's final group match, which ended in a 1–0 defeat toIreland.[35] In October 2020, after a two-year absence, Ogbonna was called into the Italian squad by manager,Roberto Mancini, for two games in theNations League.[36]
As a central defender, Ogbonna is primarily known for his outstanding physical attributes;[37][38] he is also a competent tackler, and possesses a good positional sense, as well as an ability to read the game.[39][40] He is also capable of playing as aleft back on occasion, due to his pace, technique, ball skills, vision, and distribution with his left foot.[37][38]
Ogbonna was born to Nigerian parents who emigrated to Italy from Nigeria in 1983, settling in the city ofCassino in the central part of the country, but managed to obtain Italian citizenship only after his 18th birthday.[41]
On 22 December 2008, Ogbonna survived a car accident nearTurin after he lost control of hisSmart car and drove off a bridge into atorrent at around 5:00 AM.[42]
^Pietro Ivaldi (5 February 2011)."Ogbonna, questione di testa" [Ogbonna, a matter of opinion]. La Stampa. p. 43. Archived fromthe original on 10 November 2013. Retrieved5 February 2011.
^Roberto Condio (12 February 2006)."Il Toro ai raggi X". La Stampa. p. 53. Archived fromthe original on 10 November 2013. Retrieved30 December 2010.