New York - Rafael Nadal and Roger Federer edged closer to a US Open semi-final blockbuster on Saturday as controversial Italian Fabio Fognini was kicked out for a vile, misogynistic tirade at a female umpire.
Nadal, 31, saw off Argentine lucky loser Leonardo Mayer 6-7 (3/7), 6-3, 6-1, 6-4, taking his record over the world number 59 from Buenos Aires to 4-0.
He will face Ukraine's Alexandr Dolgopolov, against whom he is 6-2, for a place in the quarter-finals.
Five-time champion Federer brushed aside 31st seed Feliciano Lopez 6-3, 6-3, 7-5 to take his career record against the Spaniard, playing a 63rd successive Grand Slam, to 13-0.
Next up for Federer is Philipp Kohlschreiber, who he leads 11-0.
Nadal had dropped the first set of his second-round match against Japan's Taro Daniel before winning in four.
Saturday was almost a carbon copy with the 15-time major winner unable to convert any of six points in the opener.
But the match turned in the 10-minute seventh game of the second set when, on his 14th break point of the encounter, Nadal finally smashed through.
"It was tough. It took 14 break points - that's not a good figure. But I was there mentally and fought a lot at the right moments," said Nadal under the Arthur Ashe roof as rain fell outside.
Federer had needed back-to-back five-setters to defeat Frances Tiafoe and Mikhail Youzhny in his first two rounds.
However, on Saturday, he swept past Lopez to reach the fourth round for the 16th time.
"I'm very happy to get through. It's a great feeling to play out here," said Federer.
"I struggled in the first two rounds but tonight I played a very clean match."
Kohlschreiber, the German 33rd seed, eliminated Australia's John Millman 7-5, 6-2, 6-4.
Austrian sixth seed Dominic Thiem defeated France's Adrian Mannarino 7-5, 6-3, 6-4 to make the last 16 for the third time in four years.
Thiem next faces 2009 champion Juan Martin del Potro of Argentina, who put out Spain's Roberto Bautista Agut 6-3, 6-3, 6-4.
Russia's Andrey Rublev became the second teenager in the last 16 when he beat Bosnia's Damir Dzumhur 6-4, 6-4, 5-7, 6-4.
Rublev, just 19, faces Belgian ninth seed David Goffin, who progressed when 2016 semi-finalist Gael Monfils retired with a right knee injury.
Meanwhile, Fognini was kicked out of the tournament for making foul-mouthed comments to female umpire Louise Engzell during his first-round loss to Stefano Travaglia.
Fognini and compatriot Simone Bolelli had reached the third round of the men's doubles but tournament organizers axed him from the event.
Fognini, the world number 26, was also fined $24 000.
Women's top seed Karolina Pliskova saved a match point to defeat China's Zhang Shuai, hanging on to her world number one spot in the process.
Top seed Pliskova, the runner-up in 2016, triumphed 3-6, 7-5, 6-4 but was forced to save a match point in the 10th game of the second set and recover from a break down in the decider.
"I was match point down and I thought I haven't tried many forehand winners down the line. That's what I did. I may not have got another chance," said the 25-year-old, who will next face Jennifer Brady of the United States.
Brady has just seven wins on the tour this year, but all have come at the Slams.
Had she lost on Saturday, Pliskova would also have been guaranteed to lose her world number one ranking to either Wimbledon champion Garbine Muguruza or Elina Svitolina.
Ukraine fourth seed Svitolina stayed in contention with a 6-4, 7-5 win over Shelby Rogers of the United States.
Russia's Daria Kasatkina reached the last 16 of a major for the first time by seeing off French Open champion Jelena Ostapenko, the 12th seed, 6-3, 6-2.
Results from day 6 of the US Open on Saturday (x denotes seeding):
Rafael Nadal (ESP x1) bt Leonardo Mayer (ARG) 6-7 (3/7), 6-3, 6-1, 6-4
Aleksandr Dolgopolov (UKR) bt Viktor Troicki (SRB) 6-1, 6-0, 6-4
David Goffin (BEL x9) bt Gael Monfils (FRA x18) 7-5, 5-1 -- retired
Andrey Rublev (RUS) bt Damir Džumhur (BIH) 6-4, 6-4, 5-7, 6-4
Roger Federer (SUI x3) bt Feliciano Lopez (ESP x31) 6-3, 6-3, 7-5
Philipp Kohlschreiber (GER x33) bt John Millman (AUS) 7-5, 6-2, 6-4
Juan Martín Del Potro (ARG x24) bt Roberto Bautista (ESP x11) 6-3, 6-3, 6-4
Dominic Thiem (AUT x6) bt Adrian Mannarino (FRA) 7-5, 6-3, 6-4
Karolína Plíšková (CZE x1) bt Shuai Zhang (CHN x27) 3-6, 7-5, 6-4
Jennifer Brady (USA) bt Monica Niculescu (ROM) 6-3, 4-6, 7-6 (7/3)
Coco Vandeweghe (USA x20) bt Agnieszka Radwanska (POL x10) 7-5, 4-6, 6-4
Lucie Safarova (CZE) bt Kurumi Nara (JPN) 6-3, 6-2
Elina Svitolina (UKR x4) bt Shelby Rogers (USA) 6-4, 7-5
Darya Kasatkina (RUS) bt Jelena Ostapenko (LAT x12) 6-3, 6-2
Kaia Kanepi (EST) bt Naomi Osaka (JPN) 6-3, 2-6, 7-5