(Reuters) - Defending champion Naomi Osaka blasted past Coco Gauff 6-3 6-0 on Saturday to end the American teenager's U.S. Open run and seal a place in the fourth round.
World number one Osaka has often struggled to replicate the form that secured her maiden Grand Slam at New York last year and the Australian Open in January, but the Japanese returned to her ruthless best to take down the talented 15-year-old.
"For me, I think this was the most focused I've been since Australia," Osaka said in an on-court interview, with Gauff beside her. "So, sorry for playing you with this type of mentality."
"Everyone was very into this match I think. I just wanted to see how she played. I think that was the biggest thing. It's been a while since I've been -- how do I say? I'm not the challenger, I guess," she added in a news conference.
Osaka will next take on Swiss 13th seed Belinda Bencic, who went through after Estonian Anett Kontaveit withdrew from their match due to an acute viral illness.
Canada's Bianca Andreescu, winner of titles at Indian Wells and Toronto during an injury-hit 2019 season, defeated Caroline Wozniacki 6-4 6-4 to advance.
Three-times winner Rafa Nadal cruised into the fourth round with a 6-3 6-4 6-2 win over South Korean Chung Hyeon and will next face 2014 champion Marin Cilic, who downed American John Isner 7-5 3-6 7-6(6) 6-4.
"Chances are not a lot, so you need to be ready to expect a very tough one," Nadal told reporters, looking ahead to the clash against the big-serving Cilic.
"I need to be focused with my serve, as always. I need to be ready to accept the challenge that brings the competition in days like these ones.
"And I hope to be ready to play my highest level, because that's what I am going to need."
German sixth seed Alexander Zverev reached the fourth round for the first time with a 6-7(4) 7-6(4) 6-3 7-6(3) win over Slovenia's Aljaz Bedene.
He was joined by Russia's Andrey Rublev who defeated Australian Nick Kyrgios 7-6(5) 7-6(5) 6-3.
Highlights of the sixth day at the U.S. Open, the final Grand Slam tournament of the year, on Saturday (times GMT):
0245 RELENTLESS RUBLEV TAMES KYRGIOS
Unseeded Russian Andrey Rublev got the upper hand in a tough opening two sets to beat Australia's Nick Kyrgios 7-6(5) 7-6(5) 6-3 at Arthur Ashe Stadium to reach the fourth round.
Earlier, Italian Matteo Berrettini overcame Alexei Popyrin 6-4 6-4 6-7(3) 7-6(2).
0040 SCHWARTZMAN SENDS SANDGREN OUT IN STRAIGHT SETS
Argentine Diego Schwartzman beat Tennys Sandgren 6-4 6-1 6-3 to advance to round four, eliminating the final American in the men's draw in the process.
0030 RUTHLESS OSAKA RACES HALTS COCO'S RUN
Defending champion Naomi Osaka beat American teen Coco Gauff 6-3 6-0 to reach the last 16, where she will face Belinda Bencic.
"(Osaka) was amazing, she's done so well in the match and I'm going to learn from this. She's been so sweet to me," the 15-year-old, who was in tears at the end, said.
2025 CILIC KNOCKS OUT HOME HOPE ISNER
Croatia's Marin Cilic beat 14th-seeded American John Isner 7-5 3-6 7-6(6) 6-4 in a battle of big servers.
Isner sent down a whopping 40 aces compared to 21 from Cilic, but converted only one of 14 break points, sending the 22nd seed through to a last-16 meeting with Rafa Nadal.
2220 ZVEREV WINS IN FOUR SETS AGAINST BEDENE
Sixth-seed Alexander Zverev beat Aljaz Bedene of Slovenia 6-7(4) 7-6(4) 6-3 7-6(3) to reach the fourth round at Flushing Meadows for the first time.
The German, who was taken to five sets in his first two matches, sent down 25 aces and 59 winners as he wrapped up the victory in three hours, 36 minutes.
2045 KONTAVEIT WITHDRAWS DUE TO ILLNESS
Estonia's Anett Kontaveit withdrew from the singles prior to her third-round match against Swiss Belinda Bencic due to an acute viral illness.
The 23rd seed is still eligible to play doubles, where she has reached the second round with Daria Kasatkina.
2020 NO SWEAT FOR NADAL IN CHUNG VICTORY
Second seed Rafa Nadal beat South Korea's Hyeon Chung 6-3 6-4 6-2 to reach the U.S. Open fourth round for the 11th time in his career.
The Spaniard, who has won the title three times and reached the semi-finals last year, cruised past Chung without facing a break point.
2010 ANDUJAR BEATS BUBLIK IN STRAIGHT SETS
Pablo Andujar beat Alexander Bublik of Kazakhstan 6-4 6-3 6-2 to reach the last 16.
The unseeded Spaniard will face either France's Gael Monfils or Canada's Denis Shapovalov in the next round.
1840 AHN OUSTS OSTAPENKO IN STRAIGHT SETS
American Kristie Ahn shed tears of joy after she beat Latvia's Jelena Ostapenko 6-3 7-5 to book her place in the fourth round of a Grand Slam for the first time.
Although Ostapenko had 28 winners to Ahn's 10, her 45 unforced errors cost her the match.
1830 SEVENTH SEED BERTENS KNOCKED OUT
Germany's Julia Goerges knocked out Dutch seventh seed Kiki Bertens with a convincing 6-2 6-3 victory on Louis Armstrong Stadium.
Goerges smashed 18 winners and converted four break points to seal progress to the fourth round where she will face Croatia's Donna Vekic.
1800 ANDREESCU ENDS WOZNIACKI'S RUN AT FLUSHING MEADOWS
Canada's Bianca Andreescu, the 15th seed, beat Caroline Wozniacki 6-4 6-4 to reach the second week of a Grand Slam for the first time.
The 19-year-old, who is making her U.S. Open main draw debut this year, hit twice as many winners as Wozniacki and also won 15 points at the net. Andreescu will face American Taylor Townsend in the last 16.
1635 UNSEEDED TOWNSEND ADVANCES
American Taylor Townsend beat Romania's Sorana Cirstea 7-5 6-2 to move into the fourth round.
Townsend converted five of seven break points and constantly approached the net to win 46 of 74 net points.
1630 MERTENS THROUGH IN STRAIGHT SETS
Belgium's 25th seed Elise Mertens beat Germany's Andrea Petkovic 6-3 6-3 in a 72-minute match to move into the fourth round.
Mertens fired seven aces and smashed 26 winners, twice that of her opponent, while also converting five of nine break points to advance.
1510 PLAY UNDER WAY IN NEW YORK
Play began on Saturday under bright sunshine with the temperature hovering around 24 degrees Celsius (75.2°F) and a forecast high of 28C. However, rain is expected later in the day.
(Compiled by Rohith Nair in Bengaluru, editing by Pritha Sarkar, Christian Radnedge, Toby Davis and Amlan Chakraborty)