Serena Williams celebrates during her straight-sets win over Karolina Pliskova. (AP: Adam Hunger)
Serena Williams has fought back from a break down in the first set to beat eighth seed Karolina Pliskova and reach the semi-finals of the US Open but defending champion Sloane Stephens has made a shock exit.
The 36-year-old Williams, who is bidding for a record seventh title at Flushing Meadows as well her 24th major singles crown, started sluggishly in the night session at Arthur Ashe Stadium, allowing Pliskova to take a 3-1 lead in the opening set before rebounding to win 6-4, 6-3.
With the heat rule in effect and junior matches on the outside courts suspended earlier in the day, Williams made 22 unforced errors in the opening set but showed all of her big-match pedigree to battle back and close out the set by winning the last four games.
“The crowd was really rooting for me and I felt so bad because everyone out here was cheering and I wasn’t winning so I thought I had to try harder,” Williams said courtside.
“I really feel like right now I’m playing free. I was having a baby this time last year so I have nothing to prove.”
The second set was far more comfortable for the 17-seeded Williams.
Two successive breaks of serve allowed Williams to win her eighth game in a row and open up a 4-0 lead, and she saw off a brief fightback from Pliskova before sending down her 13th ace to seal the match in one hour and 26 minutes.
“When I get to a grand slam, I feel I want to play really hard. I want to do really well. I love this game so maybe that’s why,” added Williams, who was beaten by Pliskova in the 2016 semi-finals.
Sloane Stephens had won two of her previous three matches against Sevastova. (AP: Andres Kudacki)
Williams was on track to meet Stephens in the semi-finals but her third-seeded countrywoman was dumped out of the tournament via a 6-2, 6-3 loss to 19th seed Anastasija Sevastova.
Stephens lacked the swagger she showed through the opening four rounds and wilted in the sun-baked daytime conditions against Sevastova, who became the first Latvian woman to reach the US Open semi-finals.
Sevastova, who avenged last year’s quarter-final loss to Stephens in New York to reach her first major semi-final, converted five of her eight break points and saved seven of the nine against her on the Arthur Ashe Stadium court.
By failing to step up her game for the key points, Stephens allowed the match to get away from her quickly and despite a late fightback, was in no shape to pull off a comeback.
Latvian world number 18 Anastasija Sevastova had previously retired from the sport. (AP: Andres Kudacki)
Stephens, who was visibly struggling under the sauna-like conditions, simply had no answer for the steady stream of drop shots sent her way by Sevastova, who later said she was not trying to take advantage of the sweltering conditions.
“I saw that she was struggling. I was struggling also a little bit, but I didn’t show it that much. But I don’t play dropshots when I see the player struggling or bending over, no,” Sevastova said.
“I just play them instinctively, and that’s how they work, or don’t work sometimes.”
Sevastova, who retired from tennis in 2013 due to injuries before returning in 2015, nearly let Stephens into the match in the second set as the American twice pulled back on serve at 2-1 and again at 4-3, but the fightback proved short-lived.
USOpen tweet: Early in her career, Sevastova retired from tennis due to injuries and disillusionment from the sport. She now finds herself in the semifinal of a Grand Slam and this is what it means
Serving for the match, the Latvian raced out to triple match point and although Stephens saved two of them, Sevastova sealed the win when the 25-year-old American pushed a backhand into the net.
“I could have s*** the bed [lost] in the first round, and that would have been really bad,” said Stephens, who is projected to drop five spots to eighth in the world rankings.
“So the fact that I made it to the quarter-finals and played some really good matches and I just competed as hard as I could, I mean [there’s] a lot to be proud of.”
Del Potro battles through
Juan Martin del Potro won the US Open in 2009, to date his only grand slam triumph. (AP: Andres Kudacki)
In the men’s draw, Juan Martin Del Potro has outslugged John Isner 6-7 (5-7), 6-3, 7-6 (4-7), 6-2 to reach the semi-finals after a towering battle in a sweltering Arthur Ashe Stadium.
More than just a three hour, 31 minute marathon, the quarter-final was a test of survival played in suffocating humidity so extreme that officials called a halt to junior matches on the outside courts for more than two hours.
Play carried on at Arthur Ashe Stadium, but with temperatures nudging 37.7 degrees Celsius, the venue was turned into a sauna, leaving two of the sport’s true heavyweights — 208-centimentre American Isner and 198cm Argentine Del Potro — suffering in the brutal conditions.
As expected with two big servers, break chances were few and far between, Isner managing just three in the entire match and unable to convert any, while Del Potro had 11 opportunities cashing in on three, including one to close out the match.
It was enough to see Del Potro, the 2009 US Open champion, through to the last four at Flushing Meadows for the third time where he will face either top seed Rafael Nadal or Austrian ninth seed Dominic Thiem, who face off later.
John Isner has never progressed past the quarter-finals at his home grand slam. (AP: Carolyn Kaster)