Promotion officials announced the matchup on Wednesday. KSW 42 takes place at the Atlas Arena in Lodz, Poland, and is headlined by a catchweight contest between middleweight king Mamed Khalidov and light heavyweight titlist Tomasz Narkun.
Gamrot claimed 155-pound gold with a unanimous decision victory over Mansour Barnaoui at KSW 36. The 27-year-old successful defended the crown with wins over Renato Gomes Gabriel and Norman Parke before a rematch with Parke was declared a no contest due to an accidental eye poke.
Szulakowski enters the bout on an eight-fight winning streak, which includes four triumphs under the KSW banner. Most recently, he scored a first-round submission win over Kamil Szymuszowski at KSW 41 on Dec. 23.