This article is part of The Next Generation series. As the greats, such as Roger Federer, Serena Williams and Rafael Nadal, become the past and Carlos Alcaraz and Iga Swiatek handle the present, The Athletic explores the next generation: the rising stars who will be tasked with securing tennis’ future.

Scan a list of junior major champions in tennis, and the names pop out. Iga Swiatek, the current women’s world No. 1 and five-time WTA Grand Slam champion. Andy Roddick, the last American man to win a major, and Andy Murray, the first British man to do so since 1936. Martina Hingis, another five-time major champion, and Justine Henin, of the French Open three-peat.

Then there are all the other names.

In the last 24 years, four boys’ Grand Slam winners have gone on to win a senior major title; eight girls’ winners have done so. Swiatek and Coco Gauff both won girls’ titles in 2018, but the last male to do the junior-senior double is Marin Cilic, who won the boys’ singles at the French Open in 2005, and the U.S. Open nine years later. Many other winners have had solid careers inside the top 50, with senior ATP or WTA titles along the way, but being an elite junior player and carrying that through to senior tennis is the opposite of a simple copy and paste.

The transition from juniors to the full tour is one of the hardest in tennis, and the tennis scoring system makes it even more so.

A point or two might be the difference between winning a junior Grand Slam title and coming second. Those points can also determine the direction of a career path. After that, injuries, finances, misfortune and form all lie in wait, along with the possibility of someone arriving who did everything you did, just better.

Junior Grand Slam tournaments carry no prize money, meaning that finance, whether familial or from tennis association support, is key to being able to attend the events; non-attendance cannot only be attributed to ability.

Then there are the elite players who skip juniors altogether, or whose progress comes later. Neither Williams sister holds a junior major title; of the men’s “Big Three,” only Roger Federer has one. Carlos Alcaraz and Jannik Sinner have six majors between them already and zero at junior level.

For this year’s boys’ and girls’ singles champions, their titles could be the start of something big. They could also be the biggest prize they will ever hold.

Australian Open

Renata Jamrichova, 17, Slovakia

Jamrichova upset the home crowd in Melbourne by beating Emerson Jones to win the girls’ singles at the Australian Open. Jones, who in September became the first Australian girl to hold junior world No. 1 since Jelena Dokic in 1998, also lost in the Wimbledon final to Jamrichova.

Jamrichova, who described the atmosphere at women’s tournaments as “bloodthirsty” in an interview with the Slovak Spectator, was 16 when she won the Australian Open. A left-hander, Jamrichova has already represented Slovakia at the Billie Jean King Cup, idolises Roger Federer but also Gael Monfils, and came from 1-4 down in the first set to beat Jones in Melbourne.

Currently playing on the International Tennis Federation (ITF) circuit, Jamrichova has already won two titles — both in 2024 — having made her ITF debut in her home country. In Trnava, she got through qualifying and made it to the last eight, where she lost to Wang Xinyu of China, who is now ranked world No. 48 on the WTA Tour.

Rei Sakamoto, 18, Japan

Rei Sakamoto was very close to being one of those players who comes second in Australia, down 3-6, 6-6 to Jan Kumstat of the Czech Republic. But Sakamoto, then 17, stormed clear in a tiebreak, propelled by his whipped forehand, before breaking Kumstat at 5-5 in the third to serve out the championship, 3-6, 7-6. 7-5.

Sakamoto, who credits Kei Nishikori and Naomi Osaka for their inspiration, had never gone beyond the third round of a junior major before his title win. Represented by management magnate IMG, he, like fellow prospect Darwin Blanch, 16, received a wildcard for this year’s Miami Open. But while Blanch got into the main draw, Sakamoto’s wildcard was for qualifying, and he lost in the first round. Ranked world No. 806, he secured his first ATP Challenger Tour win (the rung below the main tour) in November 2023, and lost to eventual champion Rafael Jodar in this year’s junior U.S. Open semifinals.

French Open

Tereza Valentova, 17, Czech Republic

Valentova, the No. 12 seed for the French Open girls’ singles, defeated another highly rated Czech and No. 3 seed Laura Samson to win the Roland Garros title. Having made her ITF Tour debut in Prague in 2023, Valentova, who is already inside the WTA top 300, has since won 5 ITF titles, including a W75, the second-highest event tier on that tour.

After beating Samson, Valentova described winning the title as the “beginning of a long road,” and her defeated finalist’s rise since is a good indication of how things can change. Valentova was injured for the 2024 Prague Open, a WTA 250 event for which she received a qualifying wildcard in 2023. Samson, who was fit to play, stormed all the way to the semifinals, knocking out multiple doubles Grand Slam champion Katerina Siniakova on the way. Despite her injury, Valentova has a 30-2 winning record at senior level for 2024.

Although their French Open final was the first all-Czech junior final in history, it perhaps shouldn’t have been a surprise: Valentova was the third Czech winner of the girls’ singles in four years, after current world No. 29 Linda Noskova in 2021, and current world No. 583 Lucie Havlickova in 2023. A fine illustration of the unpredictability in moving from the junior to senior circuit.

Kaylan Bigun, 18, USA

Bigun, who is set to play college tennis at the University of California Los Angeles, surpassed Sakamoto as junior world No. 1 after winning the French Open. Like Sakamoto, Bigun came from a set down in the final to overcome Tomasz Birkieta of Poland 4-6, 6-3, 6-3.

Bigun, a left-hander, emulated the most recent American boys’ winner in Paris, 2015 champion Tommy Paul — who nine years ago beat this year’s U.S. Open finalist, Taylor Fritz. He reached the last 16 of the Sarasota Challenger in Florida in July, and made the quarterfinals of the Las Vegas Challenger tournament in September. Bigun told the ITF that he is another tennis player who uses Lego to relax (a trait he shares with Grand Slam champions Barbora Krejcikova and Iga Swiatek), and he will be hoping to join Shelton and Emma Navarro in using college tennis as a springboard to main tour success.

Wimbledon

Renata Jamrichova, 17, Slovakia

Having come from 1-4 down against Emerson Jones at the Australian Open, Jamrichova had an easier path to a 6-3, 6-4 win on this occasion.

Nicolai Budkov Kjaer, 18, Norway

Norway is not a hotbed of men’s tennis idols, but Nicolai Budkov Kjaer came as close to his as he could get in February 2024. Drafted in to the Ultimate Tennis Showdown (UTS) event in Oslo, after the withdrawal of Dominic Thiem, Budkov Kjaer took on three-time Grand Slam finalist and compatriot Casper Ruud.

UTS, coach and social media personality Patrick Mouratoglou’s event which remakes the tennis scoring system with timed quarters, is not the ATP Tour, but it still represented a trip into the deep end for Kjaer after his Wimbledon title. Budkov Kjaer defeated Mees Rottgering of the Netherlands 6-3, 6-3 at SW19, and reached the final of the junior tournament of the U.S. Open, losing to Rafael Jodar in a third-set tiebreak.

The Norwegian, who like Ruud is sponsored by Yonex — leading to them wearing matching outfits at UTS — has won two ITF titles, and has already represented his country at the Davis Cup.

U.S. Open

Mika Stojsavljevic, 15, Great Britain

Stojsavljevic, who grew up in west London and developed as a player at Ealing Lawn Tennis Club, is now coached at the U.K. Lawn Tennis Association (LTA) National Tennis Academy in Loughborough. She won the U.S. Open title by beating Wakana Sonobe of Japan, the No. 7 seed, who Stojsavljevic also defeated at last year’s Wimbledon and U.S. Open tournaments.

Even more impressive was her semifinal win over Iva Jovic, 16. Jovic, an American, was a few points from knocking No. 29 seed Ekaterina Alexandrova out of the main draw at Flushing Meadows, and had thrashed the 15-year-old Brit in their previous meeting in Florida. After blowing Jovic away 6-0 in the first set, Stojsavljevic remained calm when her opponent took the second set, coming through 6-0, 3-6, 6-3.

The Brit won her first ITF title in Nottingham in spring 2024, but is not getting ahead of herself. “I’m just taking every day and soaking it all in,” she told Sky Sports after her title in New York.

Mika Stojsavljevic with her U.S. Open girls’ singles trophy. (Luke Hales / Getty Images)

Rafael Jodar, 17, Spain

Rafael Jodar was another junior Grand Slam winner from a set down, defeating Budkov Kjaer 2-6, 6-2, 7-6(10-1), but his path to the trophy was even tougher than that. Before meeting junior Wimbledon champion Budkov Kjaer in the final, he had to beat Sakamoto in the semifinal and home favorite Bigun in the quarterfinal, taking out all three of 2024’s previous major winners.

Jodar reached his first ITF final in July, where he lost in three sets to compatriot Pol Martin Tiffon, and he is set to follow Bigun on the college route, enrolling at the University of Virginia, where U.S. Open semifinalist and world No. 8 Emma Navarro became an NCAA champion. Its most notable recent male tennis alumnus is Brandon Nakashima. Nakashima reached the Next Gen ATP Finals in 2021 before winning the event in 2022, and he made his best run at a Grand Slam this summer in New York, reaching the fourth round.

However, he suggested after the U.S. Open that the tournament may have changed his plans.

“I think all the work I’ve been doing this season, not only this season, just in general, in my whole life, has been showed here in this tournament,” Jodar said in his post-match press conference. He will hope that there is more work to do, in Virginia or on the tour.

(Top photo of Mika Stojsavljevic: Luke Hales / Getty Images)

The Next Generation series is part of a partnership with CHANEL.

The Athletic maintains full editorial independence. Partners have no control over or input into the reporting or editing process and do not review stories before publication.