*Club domestic league appearances and goals, correct as of 15:57, 8 December 2024 (UTC) ‡ National team caps and goals, correct as of 23:14, 18 November 2024 (UTC)
Kiwior made his professional debut in 2018 for Slovak side FK Železiarne Podbrezová, before moving to MŠK Žilina in 2019 and Spezia Calcio in 2021. In January 2023, after making 39 appearances for Spezia, he transferred to Premier League club Arsenal F.C. in a deal reported to be worth £20m.[3]
Kiwior has represented Poland for all youth levels U16 and up, and made his international debut on 11 June 2022. He was selected in the Polish squads for the 2022 World Cup and Euro 2024, starting in all matches in both tournaments.
Club career
Youth career
Kiwior began playing football as a child with PUKKS Chrzciciel Tychy, before moving to UKS Grom Tychy in 2007. In 2012, he joined the GKS Tychy where he went up their youth levels and started training with their senior team. In 2016 he moved to the academy of the Belgian club Anderlecht where he finished his development, and stayed until 2018.[4]
FK Železiarne Podbrezová
Kiwior moved to the Slovak club Železiarne Podbrezová in 2018, and made his senior and professional debut with them against Nitra in the Fortuna Liga on 16 February 2019. Kiwior played the entirety of the 3–1 victory at pod Zoborom.[5]
MŠK Žilina
In August 2019, Kiwior's transfer to MŠK Žilina was announced.[6] He made his debut in the yellow jersey on 10 August 2019 during an away fixture against Ružomberok. While Žilina grabbed a three-goal lead in the first half, Ružomberok scored two in the second period and hence Kiwior was brought on to secure the defence, as a replacement for Lukáš Jánošík. Šošoni managed to keep the 3–2 win and remained undefeated in the league.[7]
Over a month later, in his second appearance, Kiwior had debuted in the starting-XI against ViOn Zlaté Moravce. While Žilina's defence remained unbeaten, the strikers had failed to score and then match concluded in a goal-less tie.[8] On 9 November Kiwior had recorded his first assist with Žilina. At Štadión pod Dubňom, Žilina was behind Ružomberok by two goals in the second half. Kiwior, a first-half replacement, managed to find Ján Bernát with a pass and narrow the score. Still, Žilina lost 2–1.[9]
During the season, he also made sporadic appearances for the reserves competing in 2. Liga.
During the coronavirus pandemic, as Žilina had entered liquidation to survive financially and had consequently released 17 players, Kiwior remained unaffected.[10]
Spezia Calcio
On 31 August 2021, Kiwior signed for Serie A side Spezia on a four-year deal.[11] He made his debut against Inter Milan on 1 December 2021 as a starter and gave away a penalty after handball that converted into goal by Lautaro Martínez.[12]
Kiwior was often deployed as defensive midfielder by his former manager Thiago Motta because of his ability to possess and control the ball.[13]
Arsenal
2022–23 season
On 23 January 2023, Kiwior moved to Arsenal on a long-term contract.[14] He made his debut against Sporting on 9 March 2023 in the Europa League last 16 first leg as Arsenal drew 2–2.[15] He made his home and Premier League debut as a substitute in Arsenal's 4–1 win against Crystal Palace on 19 March. He was handed his first start in a 3–1 win over Chelsea in early May after erratic performances from Arsenal's back line, owing to William Saliba's absence due to injury. He then started in the next game against Newcastle United, where a handball decision was overturned.[16] He helped Arsenal maintain a clean sheet in that match and gained plaudits for his performance.[17] On the final matchday of the 2022–23 season, he scored his first goal for Arsenal in a 5–0 win over Wolverhampton Wanderers.[18]
International career
On 17 May 2022, Kiwior was called up to the Polish senior squad for two 2022–23 UEFA Nations League matches against Belgium and the Netherlands.[19] He made his debut in the latter match on 11 June 2022, which ended in a 2–2 draw.[20]