[4] He scored his first-ever European goal on 3 October, in a 3–0 home win over Dinamo Zagreb in the group stage of Europa League.

[5] On 4 October 2018, Dyakov was in the starting line-up for Ludogorets in a 1–0 away loss against FC Zürich in the group stage of the UEFA Europa League and together with teammate Cosmin Moți became the player with the joint most appearances for (a) Bulgarian team(s) in European club tournaments, alongside Hristo Yovov whose record of 66 matches they equaled.

[13] Two weeks later, he marked his international début at the age of 27, with an assist[14] to a Valeri Bojinov goal in the 1–1 draw at ETO Park.

On 11 September 2012, Dyakov was sent off for a second yellow card in a 2014 World Cup qualifier against Armenia that was won 1–0 by Bulgaria.

[15] On 11 October 2013, he received a red card after being cautioned twice against the same opponent – Bulgaria lost the match held in Yerevan 2–1.

[16] On 7 February 2015, Dyakov captained his country in the 0–0 draw with Romania in a non-official friendly match, as Ivelin Popov and Nikolay Bodurov were absent from the team.