Kosiorowski started his senior career with
Korona Kielce in 2006. In the summer of 2008, he joined Scottish side
Motherwell. He left the club in mid-2010 without making a single appearance. After returning to Poland, Kosiorowski held short spells at
Jagiellonia Białystok,
Garbarnia Kraków, LKS Mogilany,
Górnik Wieliczka, and
Sandecja Nowy Sącz. In 2013, he signed for
Helmond Sport in the Dutch
Eerste Divisie and made two appearances. On 24 January 2014, he re-signed with Korona Kielce. After leaving the club in June 2015, he trialed with several teams, but remained a free agent until 2020, when he joined Gwarek Ornontowice. Kosiorowski took another break in his career in 2020 and returned to professional football in February 2023 after joining
IV liga club KS Kutno. On 4 August 2023, he signed with Marcovia 2000 Marki. == References ==