Paris - Bulgarian 10th seed Grigor Dimitrov has suffered his second successive French Open first round exit Tuesday, going down 7-6 (9/7), 6-2, 6-3 to Jack Sock of the United States.
The 24-year-old Dimitrov lost to Ivo Karlovic last year at the same stage.
Sock, the world number 37, will face either Pablo Carreno Busta of Spain or Dominica's Victor Estrella Burgos for a place in the last 32.