PARIS (AP) Roger Federer and Gael Monfils know each other - and each other's games - quite well.
Their fourth-round match Sunday will be their 13th meeting overall (Federer leads 8-4) and fourth at the French Open (Federer leads 3-0).
''Roger asks many questions,'' the 13th-seeded Monfils said, ''and I have to find many answers.''
Monfils has won their most recent two matches, both on clay, and both in straight sets.
''He's played me tough throughout my career,'' Federer said. ''Especially the last four, five years now, he's been tougher for me to play against.''
It shapes up as the most intriguing singles contest of the eight on the schedule Sunday, when rain is in the forecast.
Switzerland's Federer is, of course, a 17-time Grand Slam champion.
France's Monfils has one only major semifinal appearance to his credit, but it came in 2008 at Roland Garros, where the showman-at-heart feeds off the partisan fans' support.
''He's at home. He's very strong. He loves these kind of matches,'' the second-seeded Federer said. ''So I know the danger.''
Monfils' past two matches were five-set comeback victories, part of a 10-3 record on such occasions at the clay-court Grand Slam tournament. He's one of only two men in the professional era, which began in 1968, with 10 career five-set wins at the French Open (Harold Solomon went 10-1).
That means two things: Monfils has a way of pulling out tight matches - and he rarely reaches the latter rounds at Roland Garros with all of his energy available.
''If I could win in three sets,'' he acknowledged, ''it would be much better.''
Here's a look at what else is happening at the French Open on Sunday:
There are two other men from France in action: No. 12 Gilles Simon faces No. 8 Stan Wawrinka of Switzerland, and No. 14 Jo-Wilfried Tsonga plays No. 4 Tomas Berdych. Since 1968, there never have been more than two players from the host country in the men's quarterfinals at the French Open.
At No. 74, Russia's Teymuraz Gabashvili is trying to become lowest-ranked quarterfinalist in Paris since Ernests Gulbis was 80th in 2008. Gabashvili plays fifth-seeded Kei Nishikori, whose third-round opponent withdrew because of an injury. Nishikori can become the first Japanese man in the final eight at the tournament since 1933, when Jiro Satoh got to the semifinals for the second time.
Defending champion Maria Sharapova will take on 13th-seeded Lucie Safarova, a left-hander, on Court Suzanne Lenglen. The second-seeded Sharapova has yet to drop a set and only has lost 17 games through three matches, but she can't seem to shake a cough that's been bothering her during play. ''I have never felt like that on the court playing a Grand Slam, so this is kind of new,'' Sharapova said. ''I'm just trying to do the best that I can with the circumstances.''
CLOSE TO THE QUARTERS
The other women's matches to determine quarterfinalists will be 2008 champion Ana Ivanovic vs. No. 9 Ekaterina Makarova, No. 19 Elina Svitolina vs. No. 29 Alize Cornet, and No. 21 Garbine Muguruza vs. No. 28 Flavia Pennetta.
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