Here’s a recap of Sunday’s action from the USTA Billie Jean King National Tennis Center.
Novak Djokovic falls to Stan Wawrinka
Novak Djokovic quest to defend his US Open title is over.
Djokovic — the No. 1 player in the world — retired early in his fourth-round match at Arthur Ashe Stadium on Sunday night due to a lingering shoulder injury, giving Switzerland’s Stan Wawrinka the win.
Wawrinka was dominating early, having won the first two sets 6-4, 7-5. Wawrinka was up 2-1 in the third set when Djokovic called it, too.
Serena Williams wins again in straight sets
Serena Williams is closing in on another record, as she picked up her 99th win at the US Open on Sunday. Chris Evert has the most career wins at the tournament with 101, so Williams could own that record in a matter of days.
The No. 8-ranked Williams disposed of No. 22 Petra Martić, 6-3, 6-4 to celebrate her daughter Alexis Olympia's second birthday.
Williams started slowly with Martić winning five straight points to break the first set, but Williams came back with a vengeance. Not even an ankle injury in the second set slowed her down, as she claimed her third of four victories in this tournament in straight sets.
Williams will face No. 18 Wang Qiang in the quarterfinals. She has advanced to the quarterfinals of the US Open in each of her last 11 appearances.
Karolína Plíšková becomes second top seed to lose
The women’s bracket continued to be thrown into chaos on Sunday as No. 3 Karolína Plíšková became the second top-three seed to lose in the Round of 16, following Ashleigh Barty.
No. 16-ranked Johanna Konta nearly won the first set against Plíšková before storming back to take the match, 6-7, 6-3, 7-5.
Similarly to Barty, Plíšková has had trouble this tournament. Although she won her first match against Tereza Martincová in straight sets, it was a 7-6, 7-6 win. She only dropped five games in her second match, but her Round of 32 match went to three sets before she fell to Konta.
This is Konta's eighth win against a top-10 seeded player this year and her third in a major. She knocked off No. 9 Sloane Stephens and No. 6 Petra Kvitova in the third and fourth rounds, respectively, of Wimbledon, then beat Stephens again at the French Open when the American star was seeded seventh.
Konta will face another top-10 opponent in the next round, when she plays the winner of Elina Svitolina and Madison Keys.
Roger Federer cruises to the quarterfinals
No. 3 seed Roger Federer continued his dominating run through the US Open with his most complete win of the tournament yet.
Facing a seeded opponent for the first time in four rounds, he cruised past David Goffin in straight sets — 6-2, 6-2, 6-0 — while only dropping four total sets, a personal best this tournament.
Federer dominated with double-digit aces for the fourth straight match in New York and was particularly strong on first serves, which he won 85 percent of, a best this tournament. He was also 9-for-10 on break points, which helped him win in a clean 80 minutes.
The five-time US Open champ advanced to his 13th US Open quarterfinals, which ties him for second with Andre Agassi. Jimmy Connors holds the top mark with 17 appearances in the Open Era. He’ll face Bulgarian 28-year-old Grigor Dimitrov in the quarterfinals.
No. 18 Qiang Wang upsets No. 2 Ashleigh Barty
World No. 2 Ashleigh Barty faced trouble early in the US Open when she lost the opening set to Zarina Diyas of Kazakhstan in the first round, and Qiang Wang was able to knock Barty out of the tournament in the Round of 16 on Sunday.
Facing the 25-year-old for the first time in her career, Barty went down in straight sets 6-2, 6-4.
Barty did not break a single point in nine chances and won only 44 percent of her second serves. Her mistakes compounded quickly with 39 unforced errors in the two sets.
Wang will face Serena Williams in the quarterfinals, which begin on Tuesday.
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