The Latest: French Open champ Krejcikova tops Muguruza in NY

NEW YORK (AP) — The Latest on the U.S. Open tennis tournament (all times local):

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1:40 a.m.

Garbiñe Muguruza does not like the way her loss to Barbora Krejcikova at the U.S. Open ended.

Krejcikova took a medical timeout at 6-5 in the second set, then took her time between points in the ensuing tiebreaker of her 6-3, 7-6 (4) win in the fourth round.

After the last point, Muguruza told Krejcikova she was "so unprofessional."

At a brief session with reporters, Muguruza was asked about it.

Her response: "Well, I think, between players, you know a little bit how to behave in certain moments and, yeah, I wasn't very happy at the end of the match."

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1:15 a.m.

French Open champion Barbora Krejcikova is headed to the U.S. Open quarterfinals in her singles debut at the hard-court Grand Slam tournament after a wild 6-3, 7-6 (4) victory over two-time major champion Garbiñe Muguruza.

The eighth-seeded Krejcikova took a medical timeout while down 6-5 in the second set after saying she wanted to see the trainer for what she told the chair umpire was a diaphragm issue. When play resumed after the break, Krejcikova won seven points in a row. She also angered the ninth-seeded Muguruza by taking her time between points down the stretch.

When it ended, Krejcikova stayed in her sideline chair, hunched over, until eventually wobbly walking off the court with some assistance.

Krejcikova had participated in the main draw of singles at only four Slams — two each at the Australian Open and French Open — before collecting the title at Roland Garros in June. She also won her third Grand Slam doubles trophy in Paris.

Krejcikova then got to the fourth round in her first singles appearance at Wimbledon in July, and added this run at Flushing Meadows.

The 25-year-old from the Czech Republic plays No. 2 seed Aryna Sabalenka on Tuesday for a spot in the semifinals.

Muguruza won the French Open in 2016 and Wimbledon in 2017, and she was the runner-up at the Australian Open last year. But she has never made it past the fourth round in nine trips to the U.S. Open.

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10:50 p.m.

No. 12 seed Felix Auger-Aliassime reached the U.S. Open quarterfinals for the first time by getting past Frances Tiafoe 4-6, 6-2, 7-6 (6), 6-4 with the help of 24 aces.

Auger-Aliassime had never reached the final eight at any Grand Slam tournament until Wimbledon in July, a month before he turned 21 on Aug. 8.

Now the Canadian is the youngest man to reach consecutive major quarterfinals since Juan Martin del Potro made it to three straight in 2008-09.

Auger-Aliassime will go up against unseeded 18-year-old Carlos Alcaraz of Spain on Tuesday for a semifinal berth.

The 50th-ranked Tiafoe, a 23-year-old from the U.S., lost in the fourth round at Flushing Meadows for the second year in a row.

His best showing at a major was a quarterfinal appearance at the 2019 Australian Open.

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8:45 p.m.

Carlos Alcaraz is the youngest male quarterfinalist at the U.S. Open since 1963.

The 18-year-old from Spain reached the final eight at Flushing Meadows by beating 141st-ranked qualifier Peter Gojowczyk of Germany 5-7, 6-1, 5-7, 6-2, 6-0.

Alcaraz also becomes the youngest men's quarterfinalist at any Grand Slam tournament since Michael Chang was 18 at the 1990 French Open.

Gojowczyk is 32.

The match lasted 3 1/2 hours.

The 55th-ranked Alcaraz had upset No. 3 seed Stefanos Tsitsipas in his previous match.

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6:10 p.m.

Canadian teenager Leylah Fernandez has followed up her upset of defending champion Naomi Osaka at the U.S. Open by beating another past title winner at Flushing Meadows.

The 73rd-ranked Fernandez came back from a set and a break down to eliminate 2016 U.S. Open champion Angelique Kerber 4-6, 7-6 (5), 6-2 in the fourth round Sunday in Louis Armstrong Stadium.

Fernandez is a left-hander who redirects opponent's shots swiftly and seemingly with ease.

That's a very similar style to the one Kerber has used to reach No. 1 in the rankings and claim three Grand Slam titles.

And just like in her win against Osaka on Friday night, Fernandez dropped the opening set and trailed in the second before turning things around.

Fernandez will meet No. 5 seed Elina Svitolina in the quarterfinals.

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3:50 p.m.

No. 2 seed Daniil Medvedev cruised into the U.S. Open quarterfinals with a 6-3, 6-4, 6-3 win over Daniel Evans at Arthur Ashe Stadium.

Medvedev next plays Botic van de Zandschulp, the third unseeded player he would face at Flushing Meadows. Evans was No. 24.

Medvedev has yet to drop a set on his way to the quarterfinals for the third straight year.

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3:35 p.m.

U.S. Open qualifier Botic van de Zandschulp has reached the quarterfinals with a 6-3, 6-4, 5-7, 5-7, 6-1 win over No. 11 Diego Schwartzman at Louis Armstrong Stadium.

Van de Zandschulp won in 4 hours, 20 minutes and joined Nicolas Escude (1999) and Gilles Muller (2008) as just the third men's qualifier to reach the quarterfinals at Flushing Meadows. He had lost the first set in his first three matches.

Van de Zandschulp was part of a trio of U.S. Open qualifiers that had reached the fourth round for the first time since the tournament began keeping qualifying records in 1982. It was also the first time at any Grand Slam tournament that three male qualifiers reached Week 2 since the 1995 French Open.

The 25-year-old Dutch qualifier had already knocked out No. 8 seed Casper Ruud in the second round.

It has been a big season already for qualifiers. Russian Aslan Karatsev was a qualifier when he reached this year's Australian Open semifinals.

Schwartzman,

friends with actor Ben Stiller, lost in the first round last year at Flushing Meadows. The 29-year-old Argentine was a U.S. Open quarterfinalist in 2017 and 2019.

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1:40 p.m.

No. 5 seed Elina Svitolina beat two-time Grand Slam champion Simona Halep 6-3, 6-3 to advance to the quarterfinals at the U.S. Open.

Svitolina has never won a Grand Slam tournament. She had lost twice before to the 12th-seeded Halep in majors.

The Olympic bronze medalist, Svitolina has emerged as a contender at Flushing Meadows. She has not dropped a set in the tournament.

Naomi Osaka and No. 1 seed Ash Barty, who was upset Saturday night by Shelby Rogers, are both out of the women's draw.

No. 2 seed Aryna Sabalenka plays her fourth-round match against Elise Mertens later Sunday.

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12:25 p.m.

Jack Sock withdrew from men's doubles a day after he was forced to retire with an injury in his singles match against Alexander Zverev.

Sock appeared to suffer a leg/groin injury early in the match. Zverev led 3-6, 6-2, 6-3 and held a 2-1 lead when Sock had to call it quits.

Sock wrote on Instagram that he suffered a "minor step back for a major comeback." Sock wrote Sunday "positive news is I'll be ready to go again in a few weeks."

Sock was scheduled to play with Neal Skupski in a doubles match. The team of Dominik Koepfer and Emil Ruusuvuori took the walkover win.

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11:30 a.m.

It's another U.S. Open champion for Leylah Fernandez in her first match since she beat Naomi Osaka. Fernandez takes on 2106 champion and No. 16 seed Angelique Kerber in fourth-round action at the U.S. Open.

The 18-year-old Fernandez, out of Canada, became a breakthrough star in Flushing Meadows when the former French Open junior champion took the last two sets against Osaka to get the signature win of her career.

Osaka and No. 1 seed Ash Barty, who was upset Saturday night by Shelby Rogers, are both out of the women's draw. No. 2 seed Aryna Sabalenka plays her fourth-round match against Elise Mertens.

Men's No. 2 Daniil Medvedev plays Daniel Evans and unseeded American Frances Tiafoe tries to continue his run when he plays No. 12 Felix Auger-Aliassime.

Fernandez and Carlos Alcaraz are only 18 years old and play on Sunday. Alcaraz knocked out No. 3 seed Stefanos Tsitsipas to advance.

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