On February 28, 2014, Delija made his M-1 Global debut in the main event of M-1 Challenge 45 against Estonian Denis Smoldarev and lost via submission (keylock).
[2] On September 20, 2015, Delija faced Marcin Tybura at M-1 Challenge 61 for the M-1 Global Heavyweight Championship and lost after he suffered horrible open fracture of tibia.
Three years after injury, Delija made his comeback in the sport on May 6, 2018, in Fukoka, Japan at RIZIN 10 against Ricardo Prasel and won by unanimous decision.
[4] On November 9, 2019, Delija made his debut for Konfrontacji Sztuk Walki, in which he TKOed Englishman – Oli Thompson in the second round.
[13] On June 24, Delija defeated Shelton Graves via unanimous decision and secured his place in the 2022 PFL Playoffs.