Meet Kei Nishikori, the Rising Star Who Stunned Novak Djokovic in US Open Semi

It's possible that we just witnessed the official changing of the guard in men's tennis.

On Saturday afternoon at the U.S. Open, 10th-seeded Kei Nishikori became the first Japanese man to make a Grand Slam final when he upset world No. 1 Novak Djokovic 6-4, 1-6, 7-6, 6-3. He will play Marin Cilic, who also advanced to his first Slam final by beating a legend (in his case Roger Federer), on Monday evening.

“It’s, I don’t know, 4 o’clock in the morning,” Nishikori said moments after his upset, referring to the time back home in Japan, via Christopher Clarey of The New York Times. “But I hope a lot of people are watching.”

Japan was certainly watching, as was the rest of the world. Nishikori's breakthrough held great significance for all of men's tennis. At long last, we're seeing signs that the next generation is ready to take over from the Big Four—or, at the very least, join them on center stage.

For tennis fans, this Slam run has been a long time coming for Nishikori. After all, his tennis talent was spotted at a young age, and he moved to Nick Bollettieri's tennis academy in Florida in his early teens. He was a shy kid, and the fact that he didn't understand English at the time really made him keep to himself and focus fully on his tennis. That led to very swift progress.

At just 18, ranked No. 244 in the world, Nishikori qualified for the main draw and won his first ATP title at Delray Beach in Florida, beating veteran James Blake in the final. Later that year, he upset No. 4 David Ferrer in five sets at the U.S. Open and made it to the fourth round. That remained his best showing at this Slam up until this year.

Nishikori had many more flashes of brilliance throughout the years, but up until this week, his narrative was that while he was a great talent capable of taking down the big players—he had wins over Federer and Djokovic, and almost beat Nadal on clay this year—his body was too frequently injured for him ever to be an elite player.

In this tournament, he has turned that storyline upside down.

Nishikori came into the U.S. Open with no prep. He had to have a cyst surgically removed from his foot at the beginning of August, causing him to miss the two biggest U.S. Open warm-up tournaments, the Rogers Cup in Toronto and the Western & Southern Open in Cincinnati. He didn't even start practicing until a couple of days before his first-round match.

But that didn't seem to matter at all once play began in New York. Nishikori didn't drop a set in his first three matches, and in the fourth round, he survived a thrilling five-set match against his contemporary Milos Raonic, seeded No. 5, 4-6, 7-6, 6-7, 7-5, 6-4. That match ended at 2:26 a.m. ET and tied the record for the latest finish at the U.S. Open.

"Very happy to see a lot of people even 2:00 at the night. I don't even know how they go back home," he told reporters after the match, via USOpen.org. "Very happy to play like that. And also, thanks to my team (believing) in me until the end."

The winner of the two other latest-ever matches went on to lose in the next round, but not Nishikori. He only became more impressive, taking out Australian Open champion Stan Wawrinka, seeded No. 3, in five sets in the quarterfinals to make the first major semi of his career.

Then, just when it seemed like Nishikori had reached his ceiling, he beat the best player in the world.

Nishikori's resurgence this season—two titles and a top-10 debut—syncs up with his partnership with his coach Michael Chang, the retired American tennis player who won the French Open when he was only 17.

Julian Finney/Getty Images

Nishikori's movement, instincts and returns have always been world class, but he's added a few new dimensions to the equation, as Djokovic told the press after his loss, via USOpen.org: 

"

I think he wasn't using forehand as well as he does now. His backhand is very solid. One of the best double-handed backhands from all over the court. Really aggressive. He's very quick, so he gets a lot of balls back. Uses every short ball to attack.

"

While the 24-year-old Nishikori is only about two-and-a-half years younger than the 27-year-old Djokovic, he's a member of an entire generation of players currently under the age of 25 who have been unable to break through on the biggest stages of tennis due in part to the physicality of the sport and the unprecedented dominance of the Big Four.

In fact, Chris Chase of USA Today's For The Win points out that Nishikori is the first player younger than Djokovic to topple the Serb in a Grand Slam:

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Most of Djokovic’s major losses this decade have come to Rafael Nadal, Roger Federer or Andy Murray (who’s just one week older than Djokovic). Other losses in the past six years have come to Stan Wawrinka, Tomas Berdych, Jo-Wilfried Tsonga and Jurgen Melzer, all of whom are older than Djokovic’s 27. Before that, Djokovic was a youngster who didn’t have success against his elders. Nishikori, at 24, has Novak by three years.

"

There have been reasons to be hopeful about the future generation all year, as 23-year-olds Milos Raonic and Grigor Dimitrov made the semis of Wimbledon, and Nishikori, Raonic and Dimitrov all cracked the Top 10 at some point.

But still, few expected this from Nishikori, particularly at this tournament.

In the last two weeks, Nishikori has transformed from a question mark to a physical marvel. With a sense of belief, phenomenal on-court tactics and an ability to stay calm and focused despite the brutal conditions in New York, he's become the first member of his generation to make it to a major final.

We'll have to wait and see whether Nishikori can win his first major on Monday, and to see how he follows up his run. But maybe, just maybe, a new day in men's tennis has finally dawned.