Wins for Kei Nishikori and Jo-Wilfried Tsonga, but rain causes havoc on Day 8 at the French Open

Rain was the main topic of conversation on Sunday at the French Open as the wet stuff interfered with much of the order of play.

A lengthy delay at lunchtime forced organisers at Roland Garros to postpone the final matches of the day until Monday morning.

Frustrated fans in the French capital were resigned to miss Maria Sharapova against Lucie Safarova and Flavia Pennetta against Garbine Murguruza, while the mouth-watering tie between Roger Federer and Gael Monfils was to only play two sets before being pushed into Monday's schedule.

Those two sets were full of action, though, as Federer clinched the opening set 6-3 in just 29 minutes, Monfils found form in the second to hit back 6-4.

Federer, the world number two, is looking to beat the Frenchman for the first time in three meetings on clay but Monfils, roared on by the home crowd, will provide a stern test when the duo resume play on Philippe Chatrier.

Despite Monfils poor start there was some joy for our Gallic neighbours. Jo-Wilfried Tsonga beat fourth seed Tomas Berdych 6-3, 6-2, 6-7 (5-7), 6-3 to show the way into the quarter-finals for the rest of the five-strong French contingent.

Tsonga will play Kei Nishikori in the quarter-finals. He became the first Japanese man in 82 years to reach the French Open quarter-finals with a 6-3, 6-4, 6-2 win over Russia's Teymuraz Gabashvili.

One of the five French contingents, Gilles Simon, came unstuck against Stan Wawrinka. The eighth seed Swiss star raced into the quarter-finals by hammering Frenchman Simon 6-1 6-4 6-2 on Sunday.

The 12th-seeded Simon was blown away on a windswept court Suzanne Lenglen as 2014 Australian Open champion Wawrinka sprayed the court with winners despite the damp conditions making the clay court slower.

In the women's draw, Ana Ivanovic turned back the clock. The Serbian hitter, cheered on by her World Cup winning boyfriend Bastian Schweinsteiger, defeated Russian ninth seed Ekaterina Makarova, a semi-finalist at the Australian Open in January, 7-5 3-6 6-1 to book her eighth career Grand Slam quarter-final and first at Roland Garros since she won the 2008 title.

The French had little to celebrate on the ladies side on the draw when 20-year-old Elina Svitolina beat fellow former Roland Garros junior champion and last French woman standing, Alize Cornet 6-2 7-6 (11/9).

Svitolina, seeded 19, is only the second Ukrainian woman to reach a Grand Slam quarter-final after Kateryna Bondarenko made the last eight at the 2009 US Open.