Valavicius (25-10) made his mixed martial arts debut in 2000 as a heavyweight. In his seventh professional fight, he meet former Pride heavyweight champion Fedor Emelianenko and was defeated in the second round by submission. Following the defeat, he won thirteen of his next seventeen fights and ten of those victories came by either knockout or submission.
He has won seven of his last eight fights and only fought once in 2013, which was a victory against Dan McGlasson at Flawless FC 3. His fight against McGlasson marked only the third time he has competed in the United States as he has won two of those three fights.
During his career, fifteen of his wins have come by knockout and all of those victories have come in the first round. Overall, twenty of his twenty-five victories have come in the first round and ten of his last eleven victories have taken place in the opening round.
He is expected to make his Bellator MMA debut during the upcoming tenth season of the organization, which will begin in February.