(Changes Gencic's age to 76 after official tournament correction) (Adds details)
By Toby Davis
PARIS, June 1 (Reuters) - Novak Djokovic moved into the fourth round of the French Open on Saturday but then suffered the emotional blow of learning that the coach who nurtured his fledgling career had died.
The Serb beat Bulgarian Grigor Dimitrov 6-2 6-2 6-3 but discovered after the match that Jelena Gencic, his first coach and the person who recognised his talent, had died in Belgrade on Saturday aged 76.
The world number one broke down in the locker room after his victory and cancelled his post-match media commitments.
It was a sad end to what had been an otherwise routine day for Djokovic, whose French Open campaign gathered momentum with another impressive victory.
In contrast to his opponents in the previous rounds, Dimitrov was meant to provide a stern challenge and perhaps even cause an upset, having beaten him at the Madrid Open in May.
But Djokovic broke in the very first game and never looked like easing off as he raced to the first two sets for the loss of just four games, capitalising on a string of errors.
Perhaps the only concern during an emphatic display was an injury timeout in the third set, when the trainer was called on court to massage a problematic shoulder.
That was overshadowed, however, with the news that followed.
It was the second time Djokovic had found out about the death of someone close to him in the middle of a tournament.
His grandfather died during the Monte Carlo Masters in 2012, where he played on before comfortably losing the final to Rafa Nadal.
Gencic, a pioneer of women's tennis in the former Yugoslavia and Serbia, noticed the six-year-old Djokovic when she ran a tennis camp and then coached him for five years.
She was a versatile athlete and played tennis and handball for her country. She played in and later coached Yugoslavia's Fed Cup team.
The Serb's team had kept the news of her death a secret, and even the post-match courtside interviewer was instructed not to mention it.
Now Djokovic has a day off before he faces Germany's Philipp Kohlschreiber, who beat Romania's Victor Hanescu, in the last 16.
(Reporting by Toby Davis,; additional reporting by Zoran Milosavljevic in Belgrade; editing by Martyn Herman and Stephen Wood)