British fighter Philip De Fries is putting his KSW heavyweight belt on the line against Poland's Damian Grabowski in the main feature of the upcoming KSW 50. Ultimate Fighting Championship and Bellator MMA veteran De Fries (17-6) won the then-vacant heavyweight title at KSW 43, smashing Michal Andryszak in the opening stanza of their encounter.Since claiming the belt, “F-11” has defended it twice, submitting former champion Karol Bedorf at KSW 45 last October and securing a unanimous decision over Tomasz Narkun at KSW 47 in March of this year. In so doing, he made promotional history by becoming the first non-Polish fighter to win a KSW title and then defend it in his home country.Grabowski (22-5) went 0-3 in a tough UFC run that was plagued by bout changes due to injuries to his opponents as well as himself, but has found success since returning to his home country. He first defeated Jose Rodrigo Guelke via TKO in the opening stanza at FEN 22, then made a successful promotional debut at KSW 49, defeating Karol Bedorf in the second round.KSW 50 will go down at The SSE Arena in London on Sept. 14. At the same event, UFC veteran Norman Parke will share the cage with Poland's Marian Ziolkowki.