Bulgarian Dimitrov downed by Sock in first round

By Andrew Callus PARIS (Reuters) - Tenth seed Grigor Dimitrov fell at the first hurdle in the French Open on Tuesday, beaten in straight sets by American Jack Sock. It was the second first-round Roland Garros loss in a row for the Bulgarian, who went down 7-6((7) 6-2 6-3 to the 22-year-old Sock who had never beaten a top-20 player in a grand slam. Last year he lost to big-serving Croat Ivo Karlovic. Dimitrov, who reached the 2014 Wimbledon semi-finals, is the highest men's seed to exit this year's tournament so far. He failed to convert any of his six break points, while his opponent won three of eight. "When you don't grab those moments it's very tough to play. It doesn't matter who you are playing," said Dimitrov. "It's tough for me to accept that two years in a row I'm not just losing I'm playing a bad match." The shock result tees up a potential last-16 clash for world number 37 Sock against Rafa Nadal. Sock won his first career title at Houston -- also on clay -- in April, and reached the third round in Paris last year. In their only other encounter to date, on a hard court in Stockholm last year, Dimitrov came out the winner over the American in a tight three setter. "Obviously, that gave me some confidence going into today knowing I already played a close match with him," said Sock. "And then to play on clay, which I think suits me a little more... if I played well, I knew I had a chance. I was able to do it." (Reporting by Andrew Callus; editing by Martyn Herman and Ken Ferris)