Venus Williams sees hopes ended by Timea Bacsinszky

Venus, the former world number one is now 35, enjoyed wins over Bacsinszky at the 2008 Olympic Games and the US Open two years ago, but those matches were on hard courts.

This was their first joust on a clay court with world number nine just too good for Venus Williams, whose movement in retrieving balls from deep seemed to be a growing problem the longer the match progressed.

Switzerland's Bacsinszky will meet Kiki Bertens for a place in the semi-final.

The Dutch player reached her first Grand Slam quarter-final with a 7-6(4) 6-3 win over 15th seed Madison Keys.

The Swiss, who reached the semi-finals last year before losing in three sets to Serena Williams, kept the world number one's older sister guessing by varying the pace and depth of her play with precise groundstrokes and disguised drop shots.

Reflecting on her first win over Venus Williams in three attempts, Bacsinszky told a news conference the 35-year-old American was "definitely an inspiration ...and has been a great player for so many years."

Asked about the eight-game streak, the Swiss said she had struggled for control early on. "I tried to tell myself to move more... I was just focusing on playing deep and mixing also the rhythms... I think variation was the key."

Speaking earlier on court, she agreed it was important to have won in straight sets as "there is no longer any respite" in terms of days off between each match in a tournament ravaged by rain.

Ninth-seeded Williams, playing her 19th Roland Garros and the oldest player in the women's draw, had strapping on both knees and moved stiffly, especially in the first set, once losing her footing as she tried to reach a sliced short ball from her opponent that ended up in the net.

She sought to hit winners from sometimes unpromising positions, aiming to keep the rallies short, and in all the American notched up just six winners to Bacsinszky's 18 and 24 unforced errors against 18.

"The most disappointing part is just not playing well," Williams told a news conference.

"It was just a frustrating day of balls not going in or hitting the net tape... but I competed as well as I could out there and she played a smart match. That definitely added to my troubles."

Williams dug deeper in the second set, breaking her opponent twice in succession to level at 3-3 as she started to find her range with the heavy groundstrokes that were previously going long or finding the net.

But the Swiss broke back to lead 4-3 and held serve twice more to close out the match with her first ace.

Yulia Putintseva (Kazakhstan) beat 12-Carla Suarez Navarro (Spain) 7-5 7-5

8-Timea Bacsinszky (Switzerland) beat 9-Venus Williams (U.S.) 6-2 6-4

Kiki Bertens (Netherlands) beat 15-Madison Keys (U.S.) 7-6(4) 6-3

1-Serena Williams (U.S.) beat 18-Elina Svitolina (Ukraine) 6-1 6-1