Semerdzhiev joined Slavia Sofia at the age of seven and progressed through the Slavia academy, earning a professional contract and a place in the first team squad in the process.
On 17 May 2014, he made his senior team debut, as he came on as a substitute for Oleg Shalayev in Slavia last game of the season, a 2–0 home win over Pirin Gotse Delchev.
On 21 July 2017, Semerdzhiev was loaned to Second League club Lokomotiv Sofia.
[1] On 18 June 2018, he was loaned to another club from the second tier, Tsarsko Selo.
This biographical article related to association football in Bulgaria, about a midfielder, is a stub.