Wawrinka moves to last 8 as Djokovic retires at US Open
New York: 2016 champion Stan Wawrinka sealed his spot in the quarterfinals of the ongoing US Open as he went past defending champion Novak Djokovic at the Flushing Meadows.
On Sunday night, Wawrinka broke for a 6-4, 7-5, 2-1 lead over the World No. 1 in the fourth round when the 16-time Grand Slam champion retired due to injury.
In a rematch of the 2016 US Open final, which was won by Wawrinka in four sets, the No. 23 seed defeated the Serb for the fifth time (5-21) and he is into the last eight at the season's final Grand Slam for the fifth time in his six most recent appearances.
Djokovic, who received treatment on his left shoulder after the second set, had not lost before the quarter-finals at the US Open since 2006, when he was only 19.
Wawrinka, 34, will now face Cincinnati champion Daniil Medvedev, who secured a 3-6, 6-3, 6-2, 7-6 victory over qualifier Dominik Koepfer to book his place in the quarter-finals.
Meanwhile, Swiss legend Roger Federer crushed David Goffin in only 79 minutes to reach the quarter-finals.
Federer advanced to the US Open quarter-finals for the 13th time in his past 15 attempts by defeating Belgian 15th seed Goffin 6-2, 6-2, 6-0.
The 38-year-old, trying to stretch his men's Grand Slam record title total to 21, will now lock horns with Bulgaria's 78th-ranked Grigor Dimitrov.
18-time Grand Slam winner Rafael Nadal, who has never faced Federer at the US Open, will also return to court on Monday seeking a last-eight berth on the other side of the draw against 2014 US Open champion Marin Cilic.
Six-time champion Serena Williams and Elina Svitolina of Ukraine progressed into the quarter-finals of the US Open after registering thumping victories in their Round of 16 matches.
The 23-time Grand Slam women's singles champion defeated Martic 6-4, 6-3 to set up a last-eight date with China's Wang Qiang, who stunned No. 2 seed Ashleigh Barty 6-2, 6-4 in one hour and 22 minutes, to move into her maiden Grand Slam quarter-final.
Martic had never been past the second round of the US Open in seven trips to Flushing Meadows, and her lack of big-match experience proved costly, as Williams gained momentum and never took her foot off the pedal.
"I feel fine right now physically and obviously my state is super intense," Williams said in the on-court interview after the match. "I'm always incredibly intense. I am just trying to keep moving forward."
No. 5 seed Svitolina stunned No. 10 Madison Keys 7-5, 6-4 to move into last eight of the competition.
Svitolina will now face another first-timer in the last eight, No. 16 seed Johanna Konta of England, who
rallied past No. 3 Karolina Pliskova of the Czech Republic, 6-7, 6-3, 7-5.