 Karabelyov began to establish himself in the Slavia first team from the 2015–16 season.On 6 September 2017, he was loaned to Tsarsko Selo until the end of the year, but on 8 January 2018 Slavia shorted his loan and he returned in train with the team.Karabelyov was called up to the Bulgaria U21 squad in August 2015, aged 19.