Paris - Maria Sharapova says she's wary of the threat posed by Tuesday's French Open quarter-final opponent Garbine Muguruza but is firmly focussed on keeping her bid alive for a fifth Grand Slam title.
The Spanish world number 35 has been one of the sensations in the women's draw having knocked out world number one and defending champion Serena Williams in round two.
But Russian seventh seed Sharapova, who has won each Grand Slam once in her career, will have experience on her side against a player who captured her first WTA title in Hobart this year.
"Our job is to play the opponent that we're facing on that particular day. That's how I look at things, I don't get too far ahead of myself," said Sharapova who lifted the trophy in Paris in 2012.
"My opponent is (Garbine) Muguruza, and she's playing a great tournament. That's what I'm looking at, I'm not looking at anything else, even though I'm very well aware of other matches."
Muguruza, who overcame the challenge of French wildcard Pauline Parmentier in straight sets on Sunday, made the fourth round in Australia this year and has now gone one round better in Paris.
"I think she's a great fighter, amazing player. She has really good shots. She has been the world No. 1, so it's tough," the Venezuelan-born right hander said about Sharapova.
The winner will take on rising Canadian star Eugenie Bouchard or Spanish 14th seed Carla Suarez Navarro after both players sailed through their fourth round matches in straight sets.
Bouchard, the Montreal native, has only dropped one set all tournament.
"I'm confident and I really believe in my skills. I believe I can play with the best girls out there," said 20-year-old Bouchard who reached the Australian Open semi-finals this year.
Looking ahead to reaching her second last four slot in consecutive Grand Slams, the loss of the top three seeds means the title is there for the taking.
Barcelona resident Suarez Navarro has kept a low profile making her way into the last eight which was eased by the elimination of Polish third seed Agnieszka Radwanska.
She has now equalled her 2008 Roland Garros result, a feat she also achieved at the Australian Open in 2009 and the US Open last year.
Now she takes on Bouchard who won her first WTA event the week before Roland Garros at Nuremberg.
"She's playing good. She won one tournament last week. She was in the semi-final also in Australian Open. It's gonna be a really tough match," said Suarez Navarro.
On Wednesday, 2012 finalist Sara Errani of Italy will tackle German 28th seed Andrea Petkovic.
Errani needed 81 minutes to prise the first set 7-6 (7/5) from former number one Jelena Jankovic of Serbia before easing through the second frame 6-2.
Petkovic, who reached 2011 quarter-finals at Australia, Paris and the US Open was also pushed hard by Dutch qualifier Kike Bertens.
The Bosnian-born German prevailed 1-6, 6-2, 7-5 on the Philippe Chatrier centre court.
Romania's Simona Halep, the fourth and highest seed remaining in the draw, will face either 2009 champion Svetlana Kuznetsova or Czech Republic 24th seed Lucie Safarova.
Halep is attempting to become the first Romanian woman since her manager Virginia Ruzici in 1978 to lift the title in Paris.
Results on Monday at the French Open, the ninth day of the season's second Grand Slam tournament at Roland Garros (x denotes seeded player):
Rafael Nadal (ESP x1) bt Dusan Lajovic (SRB) 6-1, 6-2, 6-1
David Ferrer (ESP x5) bt Kevin Anderson (RSA x19) 6-3, 6-3, 6-7 (5/7), 6-1
Gael Monfils (FRA x23) bt Guillermo Garca-Lopez (ESP) 6-0, 6-2, 7-5
Andy Murray (GBR x7) bt Fernando Verdasco (ESP x24) 6-4, 7-5, 7-6 (7/3)
Svetlana Kuznetsova (RUS x27) bt Lucie Safarova (CZE x23) 6-3, 6-4
Simona Halep (ROM x4) bt Sloane Stephens (USA x15) 6-4, 6-3
Sara Errani (ITA x10) bt Jelena Jankovic (SRB x6) 7-6 (7/5), 6-2
Andrea Petkovic (GER x28) bt Kiki Bertens (NED) 1-6, 6-2, 7-5