20-year-old Australian Alex de Minaur upsets Kei Nishikori
Images from Friday, Day 5 of the US Open, in New York.
Defending champion Novak Djokovic silenced concerns about his left shoulder as he breezed past American Denis Kudla 6-3, 6-4, 6-2 on Friday to reach the last 16 at the US Open.
The Serb's title defence looked to be in jeopardy in his previous match when he received treatment on his shoulder several times, an issue which he said had impacted his serve and backhand.
But he looked to be playing pain-free against Kudla, the 16-times Grand Slam champion winning 81 percent of his first-serve points and turning aside all seven break- points he faced against the unseeded American.
Kudla, who due to a rain delay earlier this week was playing his second match in as many days, brought incredible energy into the match and raced around the court to make a number of shots that surprised Djokovic but was simply over-matched.
Up next for Djokovic is former champion Stan Wawrinka, who beat Italian Paolo Lorenzi earlier on Friday.
Serena gets closer to record-tying 24th career Grand Slam title
Serena Williams moved another step closer to a record-tying 24th career Grand Slam title with a comfortable 6-3, 6-2 victory over Czech Karolina Muchova to reach the last 16.
Wimbledon quarter-finalist Muchova held serve for an early 3-2 lead in her first career meeting with Williams but the six-times champion cranked up the pace and won the next seven games to take over the match.
"I think I had a lot of intensity today which was really good for me," Williams, who improved to 18-1 in third-round US Open matches, said in her on-court interview.
Williams took advantage of a poor serving performance by Muchova and broke her opponent five times, including in the final game where she sealed the victory when the Czech sent a forehand long.
Muchova, who reached the US Open third round last year as a qualifier in her Grand Slam main draw debut, won just 36 percent of points on her second serve, which Williams feasted on with her trademark power.
The victory for Williams was a much smoother outing than she had in her previous match, where she spent the first half of the encounter trying to find her rhythm against American teenager Catherine McNally.
Williams made 28 unforced errors against McNally and later promised to be better, a claim which she backed up as she made only 15 unforced errors in her clash with Muchova.
Up next for Williams will be Croatian 22nd seed Petra Martic, who beat Latvian Anastasija Sevastova.
Martic is in the midst of a breakthrough season in which she claimed her first title with a triumph in Istanbul and followed that up with an impressive run at the French Open where she reached her first Grand Slam quarter-final.
Federer razor sharp in win over Evans
After slow starts in his first two US Open matches, Roger Federer took his game up a notch on Friday with a stress-free 6-2, 6-2, 6-1 win over Briton Daniel Evans to reach the round of 16.
The Swiss great was brimming with confidence from the start, taking advantage of the speedy hardcourts under the open roof at Arthur Ashe Stadium on a warm and sunny day.
Federer, who is seeking his sixth US Open title, rifled 48 winners and 10 aces to see off the over-matched Evans, who is now 0-3 lifetime against the 38-year-old.
Federer has had limited court time since his epic defeat to Novak Djokovic at the Wimbledon final in July but appeared to shake off any remaining rust with the win.
"I really enjoyed myself today. Beautiful sky and you guys out here also helped," he said in an on-court interview in front of an adoring crowd.
Next up for third seeded Federer is a meeting with David Goffin, who beat Pablo Carreno Busta 7-6(7-5), 7-6(11-9), 7-5.
"They are both really quality baseliners," he said, adding that he expected the 15th seed Goffin to come out on top in his tie with the Spaniard.
"I expect it to be tough, not like today anyway."
Energized De Minaur upsets Nishikori
Alex de Minaur reached the second week of a Grand Slam for the first time after he produced an inspired performance to upset seventh seed Kei Nishikori 6-2, 6-4, 2-6 ,6-3 in the third round.
The 20-year-old Australian was in control from the outset, going up a double break in the first set and leapt in the air and pumped his fist when the Japanese sent a forehand into the net on match point.
De Minaur, nicknamed "the demon", was delighted to notch up his first win over a top 10 player.
"The crowd support was amazing," said De Minaur, who won last month's Atlanta Open for his second ATP title.
"I had a bit of a thrill last year against (Marin) Cilic," he said, referring to his heartbreaking five-set loss to the Croatian in New York.
"Was two-sets-to-love up again and I'm glad I could finally get the win."
Nishikori was far from his best, committing 60 unforced errors and seven double faults on the sunsoaked Grand Stand court.
Next up for De Minaur is either Bulgaria's Grigor Dimitrov, who overcame Poland's Kamil Majchrzak 7-5, 7-6(10-8), 6-2.
Wawrinka into last 16 after hard-fought win over Lorenzi
Former champion Stan Wawrinka fought off a spirited challenge from Italian Paolo Lorenzi to secure a 6-4, 7-6(9), 7-6(4) victory on Friday and advance to the fourth round.
Wawrinka did well to save 11 of the 13 break points he faced during the nearly three-hour encounter as he booked his spot in the U.S. Open round of 16 for the first time since he won the tournament in 2016.
In the final set Wawrinka broke Lorenzo and had a chance to serve for the match but the Italian responded with a break of his own and then held for a 6-5 lead only for the Swiss to hold to love in the next game before taking over in the tiebreak.
Up next for Wawrinka is defending champion and top seed Novak Djokovic, who was too good for American Denis Kudla, winning 6-3, 6-4.
Medvedev embraces boos to reach last 16
Russian fifth seed Daniil Medvedev overcame a hostile crowd to secure a 7-6(1), 4-6, 7-6(7), 6-4 win over Spaniard Feliciano Lopez in a tension-filled clash late on Friday and book a spot in the last 16.
Medvedev, who was heartily booed by the crowd inside Louis Armstrong Stadium at every opportunity after giving them the middle finger, relied on his powerful serve to put away Lopez and keep alive his hopes for a maiden Grand Slam title.
Playing for the second consecutive day after rain wiped out a slew of Wednesday matches, Medvedev later told the crowd that their negative energy is what carried him to victory.
"The energy you are giving me right now I think it will be enough for my next (four) matches. The more you do this the more I will win for you. Thank you," Medvedev said in his on-court interview through a chorus of boos.
"I want all of you to know when you are asleep tonight I won because of you."
The crowd turned on Medvedev in the first set when he angrily snatched a towel from a ball person's hands.
Medvedev got an unsportsmanlike conduct code violation for the incident and when it was announced, the 23-year-old tossed his racquet toward the centre of the court before telling the umpire he does not belong in the chair.
The crowd resumed their booing of Medvedev and as he walked back to his chair he decided to hold up his middle finger close to the side of his head.
When Medvedev's gesture was shown on the replay screen, the crowd showered him with boos and the umpire also gave him a talking to.
"I cannot give you a code because of what I saw on the screen. I have to see it myself," chair umpire Damien Dumusois told Medvedev.
From there, the crowd were firmly behind Lopez and used every opportunity they could to boo Medvedev, including every time he double faulted or missed a routine shot.
"I paid for it the whole match but the crowd was electric," Medvedev told a small group of reporters when asked about the inspiration he drew from the crowd.
"Even the bad energy I needed to turn it into good energy and that's why I won."
The Russian said he talked to Lopez at the net and to the Spaniard's coach, Jose Clavet, in the locker room after that match to assure them his actions were not against them and, according to Medvedev, both understood.
Medvedev also said he was not sure whether the New York crowds would continue their booing for his next match but did say he does not expect to behave the same when he takes the court on Saturday.
"I am working on myself and hopefully I will be better next time," said Medvedev.
Keys digs deep to beat Kenin
Madison Keys overcame a health scare in the second set to reach the last 16 at the US Open for a fifth consecutive year with a 6-3, 7-5 win over fellow-American Sofia Kenin.
The American 10th seed used a serving masterclass to breeze through the first set but her game noticeably dropped off in the second where she had her pulse and blood pressure checked while trailing 4-3.
But Keys, who fell to Sloane Stephens in the 2017 final and to eventual champion Naomi Osaka in last year's semi-final, returned to the court and eventually got the decisive break in the 11th game before serving out the match.
"Just not feeling 100% tonight but really glad I was able to get through in two (sets), it would have been a lot trickier if I had to go another set," Keys said.
"This was definitely a test but I'm really happy I was able to mentally get myself up."
Keys, who beat Kenin in a semi-final clash two weeks ago in Cincinnati, turned aside each of the eight break points she faced in the match, including a pair in the final game.
Up next for Keys will be Ukrainian fifth seed Elina Svitolina, who crushed Dayana Yastremska 6-2, 6-0 earlier on Friday.
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