Novak Djokovic’s day at the French Open quickly turned from light-heartedness to grief.

After making up for a recent loss to Grigor Dimitrov by beating him 6-2, 6-3, 6-3 to reach the fourth round, the No. 1-ranked Djokovic wowed the centre court crowd by addressing them in decent French afterward.

The charm reached its peak when Djokovic pledged to open a Serbian restaurant in Paris one day, drawing a roar of appreciation that could probably be heard all around Roland Garros.

Minutes later, his mood was quite different.

When Djokovic got back to the locker room, his team delivered the news that his first coach, Jelena Gencic, had died earlier on Saturday in Belgrade, Serbia, at the age of 76. She coached him for about five years, starting when Djokovic was 6.

It was the second time in a little more than a year that Djokovic has been hit by a personal loss during a tournament.

At the Monte Carlo Masters in April 2012, he learned of his grandfather’s death and decided to keep playing on, winning his third-round match just hours later. He reached the final there.

On Saturday, word was sent to reporters that Djokovic was too distraught to attend a post-match news conference.

Before that, Sunday’s fourth round men’s matches are - 17-time major champion Roger Federer against 15th-seeded Gilles Simon, No. 4 David Ferrer against No. 23 Kevin Anderson, No. 6 Jo-Wilfried Tsonga against Viktor Troicki, and No. 11 Nicolas Almagro against No. 32 Tommy Robredo.

The women’s matchups Sunday to decide quarterfinal berths- 15-time major champion Serena Williams against No. 15 Roberta Vinci, 2008 French Open titlist Ana Ivanovic against No. 4 Agnieszka Radwanska, 2009 champion Svetlana Kuznetsova against No. 8 Angelique Kerber, and 2012 runner-up Sara Errani against No. 20 Carla Suarez Navarro.

Elsewhere on Saturday, 35-year-old Tommy Haas of Germany let a record 12 match points slip in the fourth set, then saved a match point in the fifth en route to eliminating big-serving American John Isner 7-5, 7-6 (4), 4-6, 6-7 (10), 10-8 in 4 hours, 37 minutes.

Nadal overcome another sloppy start to get past 27th-seeded Fabio Fognini of Italy 7-6 (5), 6-4, 6-4.

After dropping the opening set in his first two matches, he trailed 4-2, was down a break at 6-5, and looked mightily relieved to win the tiebreaker, which was even at 4-4.

“I really need to play better,” Nadal said. “Otherwise I can go back to Mallorca and go fishing.”

“I played too short, and with mistakes.”

The Spaniard is looking to become the first man to win eight titles at the same Grand Slam tournament. He improved to 55-1 at Roland Garros despite committing 40 unforced errors and facing 11 break points.

Fognini showed off his array of spectacular shots, nearly doubling Nadal’s winners total. But the Italian let himself down just as much with some sloppy shots, making 59 unforced errors.

Fognini’s eccentricity was perfectly summed up in the second game of the second set. After missing an easy forehand at the net, he tossed his racket up in the air and tried to kick it with his foot like a skillful Italian soccer player would.

Nishikori, meanwhile, became the first Japanese man in 75 years to reach the French Open’s fourth round, beating Frenchman Benoit Paire.

“He’s a fantastic player,” Nadal said about Nishikori. “He can play very aggressive.”

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