The No. 1-seeded Murray, a three-time major champion and last year's runner-up at Roland Garros, and No. 3 Wawrinka, whose own trio of Grand Slam trophies includes the 2015 French Open, moved into the quarters with ho-hum, straight-set victories Monday. While three of the winners in women's fourth-round action Monday — No. 2 Karolina Pliskova, No. 3 Simona Halep and No. 5 Elina Svitolina — are highly seeded, none of the eight players left in that field has ever won a Grand Slam tournament. And they're all well aware. 'Everyone knows who remains in the draw,' said Svitolina, who was two points from losing before coming back to beat 290th-ranked Petra Martic 4-6, 6-3, 7-5. 'It's a big opportunity.' There's a lot more experience and hardware among the remaining men. There's Murray and Wawrinka on the top half of the bracket. On the bottom half, No. 2 Djokovic, the defending champion, and No. 4 Nadal, seeking a record-extending 10th title in Paris, would set up a showdown in the semifinals with one victory apiece Tuesday. 'Looks like one of the top four guys' is going to end up grasping the champion's Coupe des Mousquetaires, seven-time major titlist John McEnroe observed. He added that he thinks 'quite probably' the semifinals will be No. 1 vs. No. 3, and No. 2 vs. No. 4. Sure looks that way at the moment. Murray was barely tested in the fourth round, beating 21-year-old Karen Khachanov 6-3, 6-4, 6-4. Wawrinka had only a bit more trouble, eliminating the last Frenchman, No. 15 Gael Monfils, 7-5, 7-6 (7), 6-2. Next for Murray is a match against No. 8 Kei Nishikori, who got past a slow start to defeat Fernando Verdasco 0-6, 6-4, 6-4, 6-0. Murray's head-to-head record against Nishikori is 8-2. Wawrinka, meanwhile, is 11-2 against quarterfinal opponent No. 7 Marin Cilic, who was leading 6-3, 3-0 when Kevin Anderson stopped because of an injured left hamstring. Cilic knows what it takes to win a major title — he topped Nishikori in the 2014 U.S. Open final — so he appreciates his easy path. He has not dropped a set. 'It's a huge bonus for me, looking to the rest of the tournament,' Cilic said, 'knowing that, mentally and physically, I haven't spent any energy at all.' Murray did not arrive in Paris at the height of his powers, dealing with a cold and some recent shaky results. But he appears to have found his form. Dealing quite well with a swirling wind that other players complained about, Murray made only 14 unforced errors and broke the strong-serving Khachanov five times. 'Each match, I feel like I played better. I have hit the ball cleaner and started to see the right shots at the right moments,' said Murray, who became the 15th man with 650 tour-level match victories and has a .782 career winning percentage. 'Yeah, come a long way the last 10 days or so.' Wawrinka's biggest difficulty was that his lower back locked up on him early against Monfils. Wawrinka took a medical timeout midway through the second set, laying down on the sideline and getting massaged by a trainer, but then played well the rest of the way, using his sweet-swinging one-handed backhand to great effect. 'I have experienced this before. I'm not seriously worried. It doesn't keep me from playing, and it doesn't keep me from playing well,' Wawrinka said about his back. 'Let's put it this way: It's under control.' Svitolina dealt with sudden pain in her back about a half-hour before her match and said she panicked. Then it affected her play. But after trailing 5-2 in the third set, and love-30 while serving, she switched to what she jokingly called Svitolina Mode and barely a missed a shot the rest of the way. She won 20 of the last 24 points. Svitolina plays 2014 runner-up Halep, who defeated No. 21 Carla Suarez Navarro 6-1, 6-1. In another quarterfinal, Pliskova meets No. 28 Caroline Garcia, a 6-2, 6-4 winner against Alize Cornet in a match between two Frenchwomen. So what, exactly, is Svitolina Mode? 'I just try to find myself into this zone where I don't do much unforced errors,' the Ukrainian said, 'and still play aggressive.'