A forward with remarkable ball control, imagination, dribbling skills and feints, Sokolov is regarded as one of the most talented Bulgarian footballers of all time.
[2] Sokolov spent the majority of his playing career with Levski Sofia, winning two A Group titles and two Bulgarian Cups.
On 1 December 1957, he made his debut against Spartak Pleven to become the A Group's youngest ever player at the age of 15 years, 5 months and 12 days old.
[5] Two weeks later, he made his league debut for Levski in a 0–0 draw against Spartak Varna at the age of 16 years, 2 months and 12 days old.
On 13 May 1959, he became Bulgaria's youngest ever senior player by appearing in a 3–2 friendly win over Netherlands at Vasil Levski National Stadium aged 16 years, 10 months and 27 days.