Kei Nishikori stunned world No. 1 Novak Djokovic in a U.S. Open semifinal on Saturday, a shock win that came on the heels of Nishikori’s two five-set, four-hour marathons earlier this week. Though the 24-year-old Japanese player is well known to tennis fans, he’s mostly anonymous to the American public. Let’s get to know the surprise U.S. Open finalist.

1. Nishikori is the first Asian man to make a Grand Slam final.

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While Li Na has been carrying Asian tennis on the WTA in recent year, an Asian man had yet to break through at a Slam. Nishikori beomes the first. The continent will have to get up early on Tuesday morning to see him: When the match starts at 4:30 p.m. ET on Monday, it will be 5:30 a.m. in Tokyo. Speaking of Tokyo, Nishikori broke another long drought for his home country. When he defeated Stan Wawrinka on Wednesday, Nishikori became the first Slam semifinalist from Japan since 1918.

2. It was Novak Djokovic’s first Grand Slam loss to a younger player.

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That sounds crazy, but it’s true. 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.

3. In his last three matches, Nishikori beat the No. 5, No. 3 and No. 1 seeds.

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Oftentimes, a Grand Slam Cinderella takes advantage of bracket carnage and sneaks through to the later rounds without having to win a big match. Nishikori wishes he took that road to the final. The No. 10 seed had to beat No. 5 Milos Raonic, No. 3 Stan Wawrinka and No. 1 Djokovic en route to the final. To win, he’ll have to beat either No. 2 Roger Federer or No. 14 Marin Cilic.

4. Djokovic has seven Grand Slam titles. Nishikori has five tournament titles.

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You know the resume for Djokovic: World No. 1, seven-time Grand Slam champion. The CV for Nishikori is a little thinner. A consistent top 20 player, Nishikori has won five tournaments in his career. None of those were in a Masters 1000 event, the highest level of tournament outside a Grand Slams. Three of the five titles were in 250 tournaments, the fourth-tier of ATP events. (The order: Grand Slams, 1000s, 500s, 250s.)

That’s not necessarily a bad thing. Earlier this year, Wawrinka won the Australian Open without a Masters 1000 title in his pocket. (He’d later get one in Monte Carlo.)

5. Nishikori is coached by the most famous tennis player of Asian descent: Michael Chang.

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Chang is still the youngest man to ever win a Grand Slam. As a 17-year-old, the American made one of the most improbable runs in tennis history, winning the 1989 French Open. That gave Chang his first Slam earlier than higher-touted contemporaries such as Andre Agassi and Jim Courier. Chang, now 41, was a top-10 player for much of the 1990s but never won another major.

Nishikori and Chang paired up late last year, with Nishikori hoping the union would help him break through into the top 10. The pairing was supposed to last five months, but early success kept Chang on the team and it’s paying dividends now.

6. Last year, Nishikori lost in the first-round of the U.S. Open to the world No. 179.

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Winning a Slam after a first-round exit the year before would be rare, but not impossible. Serena Williams went 1R-W at the French Open in 2012 and 2013, while Steffi Graf pulled the trick at Wimbledon in 1994 and 1995.

In all, Nishikori hadn’t experienced much Slam success before these two weeks in New York. In his 20 prior major appearances, the 24-year-old advanced to just one quarterfinal.

7. No player who had ever won a match so late at the U.S. Open went on to win their next match.

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Nishikori’s late-night marathon against Milos Raonic ended at 2:26 a.m. on Tuesday morning, which tied (improbably) two other matches for the latest finish in Open history. In all, there had been four matches that set or tied the late-night record in New York. Every winner of those matches lost in the very next round. Throw in a four-hour epic with Wawrinka on Wednesday and Nishikori had spent almost twice as much time on court this week as Djokovic.

8. Toni Nadal said Nishikori outplayed Rafa on clay this year.

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This spring, Nishikori was getting the best of Rafael Nadal in the clay-court final in Madrid, but had to retire during the third set with a back injury. Nishikori’s performance greatly impressed Toni Nadal, the coach and uncle of Rafa. “We don’t deserve the victory, (Nishikori) deserves it, he played better than us the whole time,” Uncle Toni said after the retirement. That’s big praise from a guy who knows a little something about clay-court tennis.

9. Nishikori has a great record against his potential Final opponents.

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No matter who Nishikori plays on Monday, he’ll have every reason to be confident. Nishikori is 2-2 lifetime against Roger Federer and 5-2 against Marin Cilic. Also, the last time Federer played in a U.S. Open final, he was a heavy favorite against a player largely unknown in America: Juan Martin Del Potro. The Argentinian won in a five-set marathon.