[2] Nedelev started to play football at his local club and then joined the Botev 2002 Academy in 2004 when he was discovered by the owner Mr. Andrey Pavlov.

On 11 August 2012, Nedelev marked his A PFG debut with a three assists for an Ivan Tsvetkov hat-trick in a 3–0 home win over Slavia Sofia.

[8] Nedelev made his official league debut on 25 March 2014, in the 1–3 away loss against Eintracht Braunschweig after coming on as a second-half substitute for Julian Koch.

[11] On 28 February, after almost two years since his last goal, Nedelev scored during the 2-2 draw of Botev Plovdiv with PFC Pirin Blagoevgrad and he was elected for "man of the match".

[18][19] On 27 August, Nedelev provided an assist for the first goal during the 2-1 home victory over PFC Neftochimic Burgas and again received the award for "man of the match".

[27] In the next round, on 22 October, Nedelev made an assist for Radoslav Terziev goal during the 2-3 home defeat from Cherno More Varna.

[36] On 19 April, Nedelev scored from a penalty kick in the final minute and Botev Plovdiv achieved a 0-1 away victory over FC Vereya in the first leg of the semi-finals of the Bulgarian Cup.

[38][39][40] On 22 June 2017, Nedelev moved to Botev Plovdiv permanently, signing a contract for 3 years with Mainz 05, keeping the right to take half or more from the next transfer fee of the player.

[43] On 9 August, Nedelev scored a spectacular goal from a free kick against Ludogorets Razgrad, and a penalty shootout later, Botev Plovdiv won the Bulgarian Supercup for the first time in its history.

[56] On 12 March, the day when Botev Plovdiv celebrated 106 years from its foundation, Nedelev scored a goal for a dramatic 2-4 away win over FC Vereya.

[58] On 6 April, Nedelev provided a wonderful assist for Steven Petkov who scored the winning goal for the 1-0 victory over Levski Sofia.

[59] On 11 May, Nedelev again made an amazing assist for the winning goal of João Paulo da Silva Araújo and Botev Plovdiv defeated Beroe Stara Zagora with 2-1.

[66][67] During the opening round of Parva Liga, on 9 August 2020, Nedelev scored a goal, provided an assist and was selected the man of the match for the 2-0 home derby win over the local rivals Locomotiv Plovdiv.

[72] On 28 February 2023, the last day of the transfer window, Botev accepted the offer from Ludogorets Razgrad and Nedelev officially joined the club for 150 000 euros.

[75] On 9 September 2014, Nedelev came in as a substitute in the 74th minute and made an assist from a corner kick for the winning goal of Ventsislav Hristov in the opening game of UEFA Euro 2016 qualifying Group H against Azerbaijan.

[81] Thanks to the fast reactions of the Bulgaria team doctor, his injury was brought under control and the player was expected to return in play in 3 to 6 months.