Jack Sock knocked 2014 champion Marin Cilic out of the US Open in the third round on Friday, handing the seventh seed a 6-4, 6-3, 6-3 surprise.

Top-seeded holder Novak Djokovic benefited from a second straight pullout as Mikhail Youzhny quit after 31 minutes trailing 4-2 and favouring his back.

Djokovic got a free ride to the third round 48 hours earlier when Jiri Vesely withdrew injured before their match and an inflamed forearm.

The Serb moved to the New York fourth round for a 10th straight year.

Croatia's Cilic came to the final major of the season in top form after breaking through last month for his first career Masters 1000 title in Cincinnati, as he beat Andy Murray.

US player Sock stuffed any chances for the seventh seed with his victory; Cilic had won 18 of his last 20 matches at the US Open.

"For me to make the second week here and every slam going forward is my goal. I feel like if I'm playing good tennis and how I can, I feel like that's kind of where I belong," Sock said.

"I was able to piece it together today well and play a good match. Always happy to get through the next round, but definitely the hunger and excitement is that much and more. Every round you make you want to keep going and keep playing good tennis, especially in front of your home fans."

Sock drove home a point he made last season in Davis Cup play against Cilic, when he recovered from a two-sets-to love deficit to earn a win in their only previous meeting.

Sock has now reached the fourth round of a grand slam for the second time after doing so last year at Roland Garros.

Ninth seed Jo-Wilfried Tsonga dispatched South African Kevin Anderson 6-3, 6-4, 7-6 (7-4), then put on a shadow boxing display in the style of the late Muhammed Ali.

The Frenchman now leads 3-0 in the series after winning his 27th match of the season. Tonga has twice reached the New York quarter-finals.

"It's never easy to play that kind of player. He's serving well, he's also moving well from his baseline for his height," Tsonga said. "Today was a good challenge for me to beat him. I did it well, for sure."

French 10th seed Gael Monfils joined in, moving to the weekend 6-4, 6-2, 6-4 over Nicolas Almagro.

2015 women's finalist Roberta Vinci advanced past German Carina Witthoeft 6-0, 5-7, 6-3, while American eighth seed Madison Keys overcame Naomi Osaka of Japan, 7-5, 4-6, 7-6 (7-3).

Lesia Tsurenko of the Ukraine beat 12th seed Dominika Cibulkova 3-6, 6-3, 6-4.

British 13th seed Johanna Konta kept up her breakthrough 2016 progress with a 6-2, 6-1 hammering of Switzerland's Belinda Bencic.

Double Wimbledon champion Petra Kvitova took out Elina Svitolina 6-3, 6-4.

Former number one Caroline Wozniacki continued her own comeback progress as the Dane erases a first half to forget this season; she beat Monica Niculescu 6-1, 6-3 to move into the fourth round of a grand slam for the first time since a year ago at Wimbledon.

"It's been a good week so far. I'm excited to have gotten so many matches on Ashe," Wozniacki said.

"I'm happy to be here just being healthy and playing well. I'm not that worried about the ranking at this point."

Related stories

Latest news

Syrian opposition rules out future role for President al-Assad

The Syrian opposition said Friday it would not accept any role for President Bashar al-Assad in the future of the war-torn country, reacting to a recent US shift saying that removing al-Assad is no longer a priority for Washington.

Russian Army integrates breakaway forces of Georgian province

Parts of the small fighting forces of the Georgian breakaway province of South Ossetia have been placed under Russian military control, Russian Defence Minister Sergei Shoigu said on Friday.

Czech Republic's Pilsner Urquell beer is now Japanese

Japanese brewing company Asahi completed its takeover of the Czech brewery Pilsner Urquell on Friday, Asahi said in a statement.

Judge approves 25-million-dollar settlement of Trump University case

A US district judge on Friday approved a 25-million-dollar settlement of lawsuits and state fraud allegations against Trump University, the US president's now-defunct business venture.

Former Thai premier Thaksin to junta on reconciliation: 'Cut me out'

Former Thai prime minister Thaksin Shinawatra on Friday announced that he is not interested in the junta-led reconciliation process, three days after the junta handed him a half-a-billion-dollar tax bill for his past business deal.

Dalic: We welcome possible deal between Agrokor and banks

The government welcomes the possibility of an agreement being concluded between the Agrokor food company and creditor banks, and the bill on vitally important companies is not a fallback plan but the result of the government's care for the overall economic and financial stability of Croatia, Deputy Prime Minister and Minister of Economy Martina Dalic told a press conference in Zagreb on Friday.

Croatia, China sign action plan for cooperation in agriculture

The Croatian and Chinese ministries of agriculture on Friday signed an action plan for cooperation in the field of agriculture for the period 2017-2018, the Croatian ministry said in a statement.

ZSE indices up, Agrokor shares in focus of investor interest

The Zagreb Stock Exchange (ZSE) indices on Friday rose by more than 1.8%, with stocks of the Agrokor food and retail concern being in the focus of investor interest again.

Berlin police defend handling of Berlin market attacker

Berlin police defended themselves on Friday against accusations that they stopped surveillance on Berlin Christmas market attacker despite knowing in June 2016 he was dangerous.

Croatia, creditors tailor emergency measures to save tottering giant

Croatia's tottering retail and food giant Agrokor reached an agreement with its creditors, putting its debts standby and allowing it to continue working during emergency restructuring, the Croatian branch of Austria's Erste Bank said Friday.

Agrokor's creditors say standstill agreement to go into force today

A standstill agreement regarding the Agrokor concern's existing financial obligations to banks will take effect on Friday, additional capital will be injected into the concern in the coming days and the concern will be actively restructured, which includes a change of its management, it was said on Friday after a meeting between Agrokor's suppliers and creditor banks.

Palestinians, UN slam Israel's new settlement plan

Palestinians, Israeli activists and the UN lambasted the government of Israeli Prime Minister Benjamin Netanyahu on Friday, a day after it gave the go-ahead for the first new West Bank settlement in a quarter of a century.

South Sudan rebels release three abducted foreign oil workers

South Sudanese rebels have released three foreign engineers they abducted in early March in the oil-rich Upper Nile region, Foreign Affairs Ministry official Mawein Makol Arik said on Friday.

Turkish opposition: Imprisoned party chief has gone on hunger strike

The head of Turkey's pro-Kurdish opposition party has launched a hunger strike from prison.

European leagues threaten Champions League schedule clashes

The European Professional Football Leagues (EPFL) on Friday threatened schedule clashes on Champions League matchdays in an ongoing dispute with the governing body UEFA.

Danish court revokes citizenship of IS volunteer

A Danish appellate court on Friday stripped a man of his Danish citizenship for volunteering to fight for the extremist Islamic State in Syria.

Banks and Agrokor agree on key elements of standstill agreement

Member banks of the coordinating committee of financial creditors and representatives of the Agrokor food company have in principle agreed on key elements of a standstill agreement, which is expected to be signed later today, announcing changes in the company's management team, Erste Bank said in a statement on Friday afternoon.

Syrian man on trial in Sweden; mosque attack labelled terrorism

A Syrian man went on trial Friday in the southern Swedish city of Malmo, charged with terrorism and arson after an attack last year on a building used as an assembly hall by Shiite Muslims.