Born in Elin Pelin, Granchov joined the CSKA Sofia Academy in 2002 at the age of ten.

His first goal came in his second appearance, a header from a corner in a 3–1 home win against Kaliakra Kavarna on 11 March.

Granchov retained his starting spot until the end of the season, but received a red card on one occasion - in the 0–1 away loss against Ludogorets Razgrad in a title-deciding match held on 23 May 2012.

[citation needed] On 17 February 2014, Granchov signed a two-and-a-half-year contract with Lokomotiv Plovdiv.

[5] In May 2012, Granchov received his first call-up to the Bulgaria U21 team for a 2013 UEFA European Under–21 Football Championship qualification match against Scotland U21.