Sock upsets 2014 champion Cilic at U.S. Open; Djokovic wins by retirement

American Jack Sock upset 2014 champion Marin Cilic of Croatia in surprisingly routine fashion on Friday afternoon, breezing into the U.S. Open round of 16 with a 64, 63, 63 victory.

The 26thseeded Sock, who is known for his huge forehand and big serve but not for a stellar return game, broke Cilic’s serve four times in three sets to win in one hour and 41 minutes on Louis Armstrong Stadium.

Sock completely dominated his own service games, not facing a single break point in the contest.

Next up for the 23yearold American will be ninthseeded Frenchman JoWilfried Tsonga, who moved into the fourth round with a 63, 64, 76 (74) victory over 23rdseeded South African Kevin Anderson.

In another thirdround men’s singles result Friday, Serbian top seed and world No. 1 Novak Djokovic advanced to the round of 16 when Russia’s Mikhail Youzhny retired with a leg injury while trailing 24 in the first set.

Djokovic, who moved into the third round with a walkover victory over Czech Jiri Vesely, is now in the “business end” of the tournament without much match practice.

He will next take on either hugeserving American John Isner or British upandcomer Kyle Edmund, who will play Friday evening.

Mercurial 10thseeded Frenchman Gael Monfils, who has been showing the best form of his career in recent months, moved into the fourth round with an emphatic 64, 62, 64 victory over Spain’s Nicolas Almagro.

In women’s action Friday, Denmark’s Caroline Wozniacki, Italian No. 7 seed Roberta Vinci, Britain’s Johanna Konta and Czech Petra Kvitova all moved into the round of 16 with comfortable victories.

American No. 8 seed Madison Keys, however, survived a huge scare from Japanese teenager Naomi Osaka, rallying from a 51 thirdset deficit to win 75, 46, 76 (73).

In one upset in the women’s draw, Ukraine’s Lesia Tsurenko defeated 12thseeded Slovak Dominika Cibulkova 36, 63, 64.