According to A Bola, FC Porto has signed Oskar Pietuszewski. The 17-year-old is regarded as an emerging talent in Polish football. FC Porto overcame strong competition from Atlético Madrid, Betis, and Bayern.

According to agent Mariusz Piekarski, Oskar Pietuszewski was pursued by Atletico Madrid, who persisted with their efforts and had negotiated contracts. Piekarski stated that if FC Porto had failed, Atletico Madrid would have made an official offer on Monday. He added that Atletico wanted to keep the player at Jagiellonia until the end of the season. The agent also said the sporting director considered the player's opinion and acted humanely, even though the club could have earned more from a deal with Atletico Madrid.

According to Mateusz Borek, who was told by the player's agent Mariusz Piekarski, Atletico Madrid and Real Betis are strongly pursuing Oskar Pietuszewski. The 17-year-old winger is under contract at Jagiellonia Bialystok until June 2027 and has 3 goals and 2 assists in 17 appearances this season. Jagiellonia's asking price was cited as €11 million during talks in December 2025, while a minimum asking price of €15 million was reported in November 2025.