Sebastian Terteryan has long shared the spotlight with his twin brother Nikolai, and for good reason — the 24-year-old Armenian fighter brings a sharp, composed style backed by years of high-level amateur experience. A bronze medalist at the 2023 Strandja Cup and 2024 Nordic champion, Sebastian proved himself against some of Europe’s best. While his run to the Olympics ended short at the qualifying tournament in Thailand, his performances turned heads and confirmed his status as a top-tier prospect.

Sebastian’s foundation is built on family and fighting. His father, the late Tigran Terteryan, represented Armenia as a heavyweight, and his older brother remains undefeated in pro MMA. Now training in Las Vegas with Jamie Robinson, he’s well prepared for a professional career that’s been years in the making.

In June 2025, he and Nikolai signed with Golden Boy Promotions, beating out interest from several major promoters. He was initially slated to debut on the same night as his brother at Save Mart Arena in Fresno, but his fight was pulled late. Sebastian finally stepped in on Nov. 29 at the same venue, and made the wait worth it — securing an electrifying one-punch first-round KO. With his debut now checked off, Sebastian remains locked in and dangerous, carrying all the tools to make a serious impact in the middleweight division.