- Kei Nishikori the first Japanese man to make a grand slam semifinal in over 80 years
- World No. 10 is also the first to grace a U.S. Open semifinal since 1918
- He will next play world No. 1 Novak Djokovic, who beat Britain's Andy Murray
- Defending champion Serena Williams to play Ekaterina Makarova in women's semis
It had been almost a century since a Japanese man made the semifinals of the U.S. Open, but world No. 10 Kei Nishikori dug deep to ensure that unfortunate milestone was not reached.
The 24-year-old reached the last four of a grand slam for the first time in his career after a grueling 3-6 7-5 7-6 6-7 6-4 victory over third seed Stan Wawrinka.
Nishikori has endured an energy-sapping run to the semis. Before Wednesday's arduous battle with the Swiss star, he beat Canadian fifth seed Milos Raonic in a four-hour, 19-minute marathon, which equaled the latest finish to a match at Flushing Meadows, ending at 2:26 a.m.
Following his second four-hour-plus match, an exhausted Nishikori said, "My body was OK. I got more confidence, but I don't know how I finished the game."
Noted for his speed and footwork, the rising Japanese star moved the Australian Open champion around the court, despite a stuttering start, and played brightly at the net to hold out for a historic victory.
Nishikori breaks a long line of Japanese men's tennis disappointment, becoming the country's first U.S. Open semifinalist since Ichiya Kumagae's in 1918, when players were amateur and wore long pants.
He's Japan's first male grand slam semifinalist since Jiri Satoh made it this far at Wimbledon in 1933. Kimiko Date Krumm, beaten in the first round last week with her 44th birthday looming, was a women's semifinalist in three grand slams in the mid-1990s, but not the U.S Open.
Next up is world No. 1 Novak Djokovic on Saturday. "Hopefully I can play 100% tennis next round," Nishikori told reporters.
Djokovic avenged his 2012 U.S. Open final defeat by Andy Murray as he triumphed 7-6 (7-1) 6-7 (1-7) 6-2 6-4 against the British eighth seed in Wednesday's late match.
Nishikori's rise has been understated, still featured as "one to watch" on the U.S. Open website, despite his high seeding in the tournament.
Masaki Kashiwai, Head Coach of the Green Tennis School in Matsue, in Shimane prefecture, trained the nascent star until his move to the U.S.. Kashiwai said that Nishikori was obviously exceptionally talented.
"I am very proud of him," Kashiwai told CNN. "He came from the countryside to make this big in the world. He gives a dream, hope and courage to Japan's young players, professional players as well as coaches that (they) might be able to reach the top."
He first picked up a racket aged five and, at the age of 14, moved to Florida to hone his considerable talent at the IMG Academy. He couldn't speak English but, just like his wins so far in New York, he gritted his teeth and set himself to the challenge.
Former Japanese pro Shuzo Matsuoka, who "discovered" NIshikori at a tennis camp for young players in 2001, hailed his victory as "amazing" considering he wasn't in peak condition following his match against Raonic.
Matsuoka hailed Nishikori's mentality and likened the young player to his coach, former U.S. Open finalist Michael Chang.
Nishikori's result caused Matsuoka to gush: "Nothing better than having met Kei in my life. Thank you, Kei, Congratulation(s), and let's go till the end, Kei."
The ATP Newcomer of the Year from 2008 had already made history by becoming the first Japanese player to be ranked inside the ATP Tour's top 10, with a high-water mark of 9th in May of this year.
Djokovic has lost in the past three U.S. Open finals following his 2011 success, and was beaten in five out of six grand slam finals before winning Wimbledon for the second time in July.
"It's great for Kei and Japan for him to be in the semifinal. He serves and moves very well," the Serbian said after beating Murray in three and a half hours.
Meanwhile, women's No. 1 Serena Williams continued the defense of her title by reaching the semifinals with a 6-3 6-2 win over Italian 11th seed Flavia Pennetta.
She came back from 3-0 down in the opening set to keep alive her bid to become the second woman in the Open Era after Chris Evert to win the tournament three years running.
The American will next face Russian 17th seed Ekaterina Makarova, who defeated former world No. 1 Victoria Azarenka 6-4 6-2 to earn a last-four spot for the first time at a grand slam.
Makarova's only win in four clashes with Williams was at the 2012 Australian Open, but the 32-year-old -- seeking to join Evert and Martina Navratilova on 18 grand slam titles -- is wary of her younger, left-handed opponent.
"Makarova moves well. She doesn't care who she plays, she gives 100%. Those types of players are often difficult to play because it makes them better," Williams said.
"She also has that serve that can go out wide, or you never know where it's going to go. She has a great backhand and she's improved her forehand."
Date-Krumm, meanwhile, earned a place in the semifinals of the women's doubles on Wednesday -- the first time she has done so in her long career.
The Japanese veteran, who reached a quarterfinal in 1992, made the breakthrough in partnership with Czech Barbora Zahlavova -- 15 years her junior -- as they beat eighth seeds Andrea Hlavackova of the Czech Republic and Zheng Jie of China.
They will next take on Makarova and her fellow Russian Elena Vesnina, the fourth seeds who knocked out the Williams sisters in their quarterfinal on Tuesday.
"I cannot believe it myself," Date-Krumm said. "Recovery is difficult at my age, but I'm enjoying every moment with Barbora."
The other semifinal will feature former world No. 1 Martina Hingis, who with Pennetta will be seeking the ninth women's doubles title of her career -- but the first since 2002.
They will take on third-seeded Cara Black of Zimbabwe and Sania Mirza of India.