Michał Marcjanik joined Polonia Warszawa after his contract with Arka Gdynia expired. Marcjanik's agreement with Polonia Warszawa is valid until June 30, 2028, and includes an option to extend.

According to Tomasz Włodarczyk of Meczyki.pl, 31-year-old Polish central defender Michał Marcjanik is set to join Polonia Warszawa this summer. His contract at Arka Gdynia expires at the end of June. Arka Gdynia had attempted to keep the player and entered into negotiations over an extension, but the parties failed to reach an agreement. In a March interview with Trojmiasto.pl, the club's president, Wojciech Pertkiewicz, stated that they were past a second round of talks and that another was planned. Pertkiewicz also stated that he was negotiating directly with Marcjanik, not his manager. Marcjanik joined Arka Gdynia in August 2020. According to Transfermarkt, his current market value is €200k. He has two caps for the Poland U21 national team, and Miedź Legnica had also been linked with the player.