Defending champion Naomi Osaka has been knocked out of the US Open, losing 7-5 6-4 to Switzerland’s Belinda Bencic in the last 16.

Osaka, 21, was broken late in the opening set and then again in the fifth game of the second under the Arthur Ashe Stadium roof at Flushing Meadows.

Japan’s Osaka will lose her world number one ranking, with Ashleigh Barty of Australia to return to the top spot.

Bencic, the 13th seed, will play Donna Vekic in the quarter-finals.

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The Croat, seeded 23rd, saved a match point as she beat Germany’s 26th seed Julia Gorges 6-7 (5-7) 7-5 6-3 in two hours and 42 minutes on Louis Armstrong Stadium.

For Bencic, 22, it is her second appearance in the quarter-finals after also making the last eight in 2014 as a 17-year-old.

She has now beaten Osaka three times this year after previous victories in Indian Wells and Madrid.

“I was so excited to come on the court, the challenge cannot be bigger – Naomi Osaka is a great player and won the US Open last year,” said Bencic. “I had to be on top of my game and am really pleased with how I played.

“She has a lot of power, I was just trying to play it a little bit like chess, anticipate and make a tactic on the court.”

Osaka, who beat Serena Williams in last year’s final for her maiden Grand Slam title, started off badly as she lost her serve at the first opportunity and had to save two break points to avoid going 3-0 down.

She then fought back with a break before Bencic took the decisive break in the 11th game and then served out the set.

In the second set, Osaka, who later said she had been struggling with a knee injury, double-faulted to gift Bencic another break and the Swiss player took the final game of the match with a service hold to love.

After winning the Australian Open in January for her second Grand Slam, Osaka became the world number one, a position she held until June when Barty took over.

Osaka returned to the top eight weeks later but Barty will become number one again, despite losing in the last 16 to China’s Qiang Wang on Sunday.

“For me, right now I have this feeling of sadness, but I also feel like I have learned so much during this tournament,” said Osaka, who received wide praise for comforting 15-year-old Coco Gauff, with both players crying after their third-round match.

“I feel like the steps I’ve taken as a person have been much greater than I would imagine at this point, so I hope I can keep growing. I know if I keep working hard, then I’ll have better results.”

Vekic comes back from brink to beat Gorges

Bencic’s quarter-final opponent will be 23-year-old Vekic, who is through to the last eight of a Grand Slam for the first time after a superb recovery against Gorges.

Germany’s Gorges served for the match when leading 5-4 in the second set but appeared overcome with nerves, coughing up three double faults among a series of errors.

She did have a match point but netted a forehand and when a serve-volley went long, Vekic was back at 5-5. The Croat then broke again in Gorges’ next service game to take the second set.

A single break in the decider left Vekic serving for the match at 5-3 and she had to save two break points before a Gorges smash went over the baseline to give her the victory.

“She was serving for the match, had match points but I just kept fighting and believing I could win,” said Vekic.

“I was just trying to get a return in the court, she was serving amazing, but I felt confident in the rallies.”

On facing Bencic, Vekic added: “She is a really good friend of mine, we practise together often and know each other’s game pretty well. She’s one of the best players this year.”

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Karolina Pliskova was one of the favourites to win the US Open title, but was beaten by Britain’s Johanna Konta in a compelling last-16 match.

In her final BBC Sport column from New York, the Czech third seed talks about her exit at Flushing Meadows, why it has not changed her belief she can win a Grand Slam – and her love for fishing.

Losing to Johanna Konta was disappointing but I would not say this was another golden opportunity missed to finally win my first Grand Slam.

I played an opponent who has been fourth in the world, so it was always going to be very hard, and then she played the best I’ve seen her play.

And even if I had won, I would have played Elina Svitolina, and possibly Serena Williams in the semi-finals, so there would not be an easy match between now and the final.

Maybe the first couple of matches were a little easier than they sometimes they can be, but this was not a dream draw for me. The standard is so high in the women’s game but I’m still sure I have the game to win a Grand Slam – that remains the goal.

Overall, I played solid in the tournament – it was not a disaster and it was nothing super. I could do much better.

Leading by a set and a break against Johanna meant it was, of course, a big chance but it is not like I missed match points – it was very close all the way through the match.

Immediately after losing a match like that, I don’t feel angry. You have a lot of emotion and stress during a tournament so once you lose it is like all those emotions are suddenly lifted.

‘She said she had improved since Rome – she was 50 times better!’

It is tough to talk about positives because I don’t see any.

Maybe it was my best match of the tournament but sometimes it is not enough when somebody plays as well as Johanna did. I had beaten Johanna in six of our seven previous meetings at tour level, but she played more aggressive than our other matches.

She said before she thought she had improved since I beat her in the Italian Open final in Rome – and I think she was 50 times better!

What impressed me the most was the way she went for her shots a little bit more, because normally I think she waits more for mistakes from her opponent, or plays more crosscourt, but she went for every shot and a lot of times she hit the line. She was brave and it paid off.

She also served very well, especially in the third set when she was behind on serve and I was always one game up. She did a great job by serving under pressure and putting the pressure back on to me.

Overall I’d say it was her best match of the tournament so far, but it is tough to say how far she can go.

She has reached this part of a Grand Slam a few times now, and semi-finals, but I’m not sure if she can go on to win it because Serena Williams and Naomi Osaka are still in the draw, while Elina is going to be tough in the next round.

‘A chance to catch up with family – but no time for fishing’

I will not watch the rest of the tournament because of the time difference – I am flying back to Prague straight away – and there is nobody who I would be interested in staying up to watch.

When I get to Prague I will take some time off because the month has been long and I haven’t had many days off. Then I will think about my plan, and then the Asia swing which starts later this month.

My twin sister Kristyna is already back in the Czech Republic so we will spend time with our family because we are away a lot, and maybe I will go home to Monte Carlo for a couple of days too.

I will also get to see our little sister – she is six and starts school this week. She is very excited about that. She is very clever, I think more than most six-year-olds, so she should do very well at school and enjoy it.

Obviously I wish I was still going to be here in New York all week, but at least it will be nice to see her going to school on her first week there.

Other than that, I will be sleeping, shopping and doing all the normal stuff – although I doubt I’ll have time for fishing, which is one of my favourite hobbies!

I like fresh water fishing a lot. The Czech Republic has no coast so I fish in rivers, ponds or lakes.

You need a licence to fish so I have one of those and I know more about the waters there, although I went deep-sea fishing in the Seychelles and Miami last year to try different things.

My father is a big fan of fishing – that’s where I get my love from – and he tries to teach me how to fish when we go. But I never catch any big fish!

If you want to catch smaller fish then it is easier because you could possibly catch one every 20 or 30 minutes, but if you want to go for bigger weights then you need to be sitting there for hours and hours – maybe all night.

It is a relaxing hobby. I don’t have my phone on when I’m fishing because you need to be focused and quiet, so it can be helpful for the mental part.

Once my tennis career is over I want to go fishing more, but for the moment I only have one or two days off every now and then so I don’t get the chance.

Karolina Pliskova was talking to BBC Sport’s Jonathan Jurejko at Flushing Meadows

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Defending champion Novak Djokovic is out of the US Open after quitting because of injury against Swiss 23rd seed Stan Wawrinka as defeat loomed in an electrifying fourth-round match.

Djokovic, 32, retired with a shoulder problem seconds after a double fault left him two sets and a break down.

Loud boos greeted the Serb’s decision, with more heard as he walked off court.

“I’m sorry for the crowd. They came to see a full match but it wasn’t to be,” said world number one Djokovic.

Three-time Grand Slam champion Wawrinka had dominated the last-16 contest in a boisterous atmosphere at Arthur Ashe Stadium, producing a powerful display reminiscent of his best to lead 6-4 7-5 2-0, when Djokovic decided he could not continue.

Wawrinka, 34, will play Russian fifth seed Daniil Medvedev in the quarter-finals.

‘You know when you’re not able to hit the shot any more’

Djokovic was the hot favourite to retain his title at Flushing Meadows and win a 17th Grand Slam, which would move him closer to Roger Federer (20) and Rafael Nadal (18) in the race to be deemed the greatest men’s player of all time.

But he had been hampered throughout the tournament with a left shoulder injury, which he says has left him in “constant pain for a few weeks”.

Djokovic particularly struggled during his second-round match against Argentina’s Juan Ignacio Londero on Wednesday, needing intense treatment three times before coming through in straight sets.

Before his next match against American Denis Kudla, there had been speculation he might withdraw because of the problem, only to show few signs of the issue in a comfortable win on Friday.

But Djokovic said the intensity of the pain returned against Wawrinka.

“It is very frustrating. Of course it hurts that I had to retire,” said the Serb.

“Some days the pain has been higher, some days with less intensity. Obviously I was taking different stuff to kill the pain instantly. Sometimes it works, sometimes it doesn’t.

“You just know when you know, when you feel like you’re not able to hit the shot any more.”

The Serb did not want to discuss the near 24,000 crowd’s reaction to his early exit, while Wawrinka said he was surprised by negativity.

“He’s an amazing champion,” added the Swiss. “If he has to retire, it’s not the best for a tennis player to have to leave the court like that.”

Djokovic suggested he hopes to regain fitness for the Asia leg of the ATP Tour and the final months of the season.

“It’s no secret that I have desire and a goal to reach the most Grand Slams, and reach Roger’s record,” he added.

“At the same time, it’s a long road ahead hopefully for me. I hope I can play for many more years. I’m planning to. I don’t see an end behind the corner at all.”

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Wawrinka delighted with impressive performance

Djokovic’s withdrawal failed to take the shine off a breathtaking performance from Wawrinka, who earned his biggest victory since beating Britain’s Andy Murray, then world number one, in the 2017 French Open semi-finals.

Shortly after that run, Wawrinka’s career stalled because of a left knee injury, which left him needing two operations.

It has been a slow climb back up the rankings for the former world number three, but proved he could still cause problems for the best – whatever their physical state – in a powerful display.

Wawrinka came out firing from the start, piercing Djokovic’s famed defence with blistering groundstrokes as he broke for 3-2 and producing thumping aces to stave off a break point in the next game on his way to clinching the opener.

Wawrinka had beaten Djokovic three times at a Grand Slam – including their last meeting in the 2016 final at Flushing Meadows – having lost the opening set in each of them.

This proved different, despite Djokovic coming out fighting by holding to love in the first game of the second set, and then breaking to gain an early advantage.

Wawrinka, backed by a vociferous New York crowd, was soon level after breaking back in a pivotal seventh game in which Djokovic coughed up two double faults serving for a 5-2 lead, and the Swiss landed a beautiful one-handed backhand down the line which left some fans climbing to their feet in admiration.

Djokovic started to look rattled by the injury and the atmosphere, coming up with poor shots as he tried to respond, allowing Wawrinka another break and the chance to serve out for a two-set advantage.

Treatment at the changeover was a last-ditch attempt by Djokovic to improve his physical – and perhaps mental – state, but it did not prove successful and he quit a few minutes later.

“I’m sorry he had to retire to finish the game like that, but for me, most important is the way I’m playing, the way I’m moving,” Wawrinka said.

“The more the match was going, the better I was playing. I was hitting the ball really hard. I was feeling great on court.”

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Analysis

Russell Fuller, BBC tennis correspondent

Wawrinka had been in rampant form. He was pummelling the ball and reminding us of the man who, before knee surgery, had won three Grand Slam titles.

Djokovic was, however, very subdued. He seemed to be observing events, rather than influencing them.

Only he knows whether he could have finished the match, but to leave the court with boos ringing in his ears was a very harsh send-off for a 16-time Grand Slam champion.

The odds on Nadal and Federer will now shorten further. But perhaps we do need to look outside the top three for a potential champion.

Wawrinka might be 34, but when he reaches the second week of a Grand Slam in this kind of mood he can be very difficult to stop.

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