Serena Williams is two wins away from her record 23rd Grand Slam title.
Williams, the top seed in the U.S. Open women's singles draw, knocked off No. 5 Simona Halep 6-2, 4-6, 6-3 to advance to the semifinals. Halep won a tense second set, but Williams dominated the third to advance to the 11th U.S. Open semifinal of her career.
In Wednesday's night session finale, Stan Wawrinka beat Juan Martin del Potro in four sets to advance to the men's semifinals.
See below for a closer look at Wednesday night's results.
For news and results from Wednesday's day session, including victories by Karolina Pliskova and Kei Nishikori, check out SI.com's recap.
No. 1 Serena Williams d. No. 5 Simona Halep: Serena Williams is back in the U.S. Open semifinals after beating Simona Halep in three sets, 6-2, 4-6, 6-3. Williams got the win, but it wasn't as smooth as it could have been—she forced 20 break point opportunities and only converted four. She also hit 43 unforced errors, though she did tally 50 winners.
"I'm glad I got tested," Williams said. "I think her level really picked up in the second, but I had some opportunities that I didn't take. So what I gather from that is I really could have played better in that second set and maybe had an opportunity to win in straights. I think if anything, that's the biggest silver lining I take."
In the semifinals, Williams will face Karolina Pliskova, who beat Ana Konjuh earlier on Wednesday after knocking out Venus Williams in the fourth round. In their sole meeting, Williams beat Pliskova in straight sets in 2014.
Last year, of course, Williams lost in the semifinals to Roberta Vinci. Williams is seeking the seventh U.S. Open title of her career.
With her win on Wednesday, Williams improved to 8-1 against Halep over her career.
No. 3 Stan Wawrinka d. Juan Martin del Potro: The match finally ended at nearly 1:30 a.m., when Stan Wawrinka closed out Juan Martin del Potro in four sets, 7-6(3), 4-6, 6-3, 6-2. How different a match this could have been: Del Potro held a 4–1 lead in the first set, and lost a tiebreaker 7–3. He won the second set, but ultimately he didn't have enough—particularly in terms of his stamina—to hang with Wawrinka.
Lest we forget, Del Potro just returned from a long injury spell in February, and the fitness disparity showed on Thursday. Wawrinka, who won a five–set marathon earlier this tournament against Daniel Evans, was clearly better prepared for a marathon match. It didn't go five, but the match still lasted more than three hours.
Wawrinka exploited Del Potro's glaring weakness: his backhand. Del Potro always favors his forehand, but Wawrinka is unusually well–positioned to exploit that flaw because of his exceptionally strong backhand, which Wawrinka used to pin Del Potro in his ad side corner before running him to the deuce side with a laser backhand down the line.
Del Potro also suffered from self–inflicted errors: He double–faulted eight times, while Wawrinka avoided double–faulting altogether.
Wawrinka will face Kei Nishikori in the semifinals. Wawrinka is 3–2 against Nishikori all–time, including a five–set loss at the 2014 U.S. Open, when Nishikori reached the final.
Reason No. 348 why we love DelPo
This post–match tweet.
Here's a weird fact
GIF of the Night
For Juan Martin del Potro, this was the story of the first set: frustration.
Tweet of the Night Part II
Check back on Friday for results from the women's singles semifinals, featuring Serena Williams vs. Karolina Pliskova and Angelique Kerber vs. Caroline Wozniacki.