KSW 43 takes place in Wroclaw, Poland, on April 14, and will see hometown favorite Damian Janikowski headline the card against Yannick Bahati. Additionally, Roberto Soldic will defend the welterweight strap against Dricus Du Plessis.
Parnasse was successful in his first promotional foray, as he took a majority verdict over Lukasz Rajewski at KSW 41 on Dec. 23. The 20-year-old owns a 10-0-1 career mark since beginning his professional tenure in 2015.
Sowinski, a longtime KSW veteran, is coming off a third-round submission defeat to Kleber Koike Erbst at KSW 41. The 30-year-old Pole is 18-9 with two no contests over the course of his pro tenure.