M-1 Global Three years after retiring in 2008, Semenov returned to MMA and fought
Luigi Fioravanti at
M-1 Challenge: 25 on April 28, 2011. Though a considerable underdog on media scoring websites, Semenov won the fight via unanimous decision. After another hiatus, Semenov returned on December 8, 2012, facing Michele Verginelli at
M-1 Challenge: 36. He won via unanimous decision. Semenov fought on October 20, 2013, defeating Gregor Herb at M-1 Challenge 42. He was then scheduled to face Ramazan Emeev at M-1 Challenge 47 on April 4, 2014, however in the weeks leading up to the event, the bout was cancelled for unknown reasons.
Ultimate Fighting Championship With a 20-2 record, Semenov made his UFC debut on January 11, 2002, against notable BJJ black-belt
Ricardo Almeida at
UFC 35. Semenov won via TKO (punches). He returned four months later on May 10, 2002, facing
Ivan Salaverry at
UFC 37. Semenov lost via TKO, and following the fight, Semenov left the UFC and returned to the M-1 Global promotion. ==Championships and accomplishments==