On 4 March 2011, Tsvetkov returned to Bulgaria and signed for Pirin Blagoevgrad on a rolling contract until the end of the season.

[4] On 2 April, in a 3–0 home victory over Montana, he netted his first goal in an A PFG match and assisted Krum Bibishkov and Anton Karachanakov.

On 21 May, he netted from a free-kick in a 1–1 home draw against Chernomorets Burgas, securing Pirin's place in the top flight for the next season.

On 2 July, he made his unofficial debut and netted the only goal in the 1–0 win against Lokomotiv Sofia in an exhibition match, which marked the end of former Bulgarian international Georgi Markov's professional football career.

[8] His official debut for Levski came on 28 July 2011 – he played the full 90 minutes in the 2–1 win over Slovak side FC Spartak Trnava in a UEFA Europa League match.

[10] On 28 October 2011, Tsvetkov made his first appearance in The Eternal Derby of Bulgaria, coming on as a late substitute in the 0–1 loss against CSKA Sofia.

[13] In June 2012, Tsvetkov signed a two-year contract with newly promoted A Group side Botev Plovdiv.

[14] In his debut for Botev on 11 August 2012, Tsvetkov scored a hattrick and missed a penalty kick to help his team to a 3–0 home win over Slavia Sofia.

On 12 October 2013, Tsvetkov marked his return with a goal in the 3–0 win over Neftochimic Burgas in a Bulgarian Cup match.

[21] His excellent performance continued on 30 August 2014 during the 7th round of A Group when he scored a goal and made an assist during the second half of the game with Haskovo.

[22] On 12 September, Tsvetkov was brought on as a substitute in the match against Ludogorets Razgrad and scored his 4th goal for the season from a penalty kick.

[24] On 27 September, Tsvetkov played his 100th match in the league and scored a goal for the 2–0 win over the local rivals Lokomotiv Plovdiv.

[33] In November 2012, Tsvetkov was called up to the Bulgaria national team by head coach Lyuboslav Penev for a friendly match against Ukraine.