In 2020, a 12yo tennis prodigy from Lienz, Austria made a bet with her coach: if she won her next junior tournament, she could switch to a one-handed backhand.

She won the tournament, and made good on her bet.

Five years later, still just 17yo, she has a junior Slam title and a WTA 250 final on her resume.

Her coach won Roland-Garros.

Her manager runs Jannik Sinner's career.

And she’s one of the most promising prospects on the WTA Tour.

It's Tuesday, so here's One to Watch... Lilli Tagger.

The Tagger family runs on tennis the way some American families run on faith or football. Father Stephan played in the Austrian Bundesliga and mother Sabine competed in the Damen Bundesliga, the top women's league in the country. When the three kids, Ben, Emma, and Lilli, started getting serious about competition, the parents spent years driving across Austria for junior tournaments.

Three age groups, one car, and a whole lotta trophies.

The path out of East Tyrol, Austria ran through Italy. Brother Ben saw Jannik Sinner play at the Vienna Stadthalle one night and noticed he was from Innichen in South Tyrol, three hours from Lienz by mountain road. That led the family through a chain of alpine coaching connections to Sinner's manager, Alex Vittur, who took Tagger on as a client.¹

At 13, with a contract from Patrick Mouratoglou's academy already drafted, Vittur told the family to walk away from the deal, saying the clauses were too restrictive and the machine was too big.² Instead, they accepted an offer from Massimo Sartori's academy in Vicenza before making the leap to Francesca Schiavone's academy in Varese. Schiavone, the 2010 Roland-Garros champion, famous for her own one-handed backhand, would come on board as Tagger's traveling coach.

In early 2025, Tagger and Schiavone set the girls' title at Roland-Garros as their primary target for the year, building the Austrian's entire spring schedule around it. In June, Tagger dropped just two games against Hannah Klugman in the championship match, becoming the first Austrian ever to win a junior slam title in singles.³

The numbers from the last fourteen months tell a compelling story. From #755 in January 2025 to #115 on this week's WTA rankings. Lifting trophies at four ITF levels. Reaching the finals in her WTA main draw debut in Jiujiang, saving three match points against Viktorija Golubic in the semifinals, and a final at the WTA 125 in Mumbai just last week.

A deeper dive into the stats shows promising signs of mental toughness and tactical range. In deciding sets over the last year, for instance, she is 10-2. In Mumbai, she fired 33 aces on her way to the final, carving up opponents with a slice backhand that sets up for a forehand kill shot.

The connection to Jannik Sinner runs deeper than shared management. The pair trained together during the preseason, share the same youth coach in Heribert Mayr, and grew up on opposite sides of the same alpine border. When asked about Tagger at last year's Vienna tournament, the Italian kept it simple. She "goes on the court and plays, doesn't talk much, has a good mentality." Then, without much hedging: "She has all the talent to reach the top of the world."⁵

Tagger's immediate target is a French Open main draw entry, nine months after winning the junior title with Schiavone courtside.

Now living on her own in an apartment in Milan, Tagger is self-sufficient well beyond her years. She cooks for herself, strings her own rackets,⁴ and attends school online in Italy, the same one former Italian ATP pro Andreas Seppi once used.

Truly, Lilli Tagger has been making her own calls since she was 12.

¹ LAOLA1. "Aus Lienz in die Welt: Lilli Tagger und ihr Tennis-Marchen." LAOLA1, May 22, 2025. link

² Tennis Magazine Italia. "Il neozelandese, Sartori, Schiavone e il rovescio a una mano: Welcome Lilli!" Tennis Magazine Italia, June 11, 2025. link

³ Ramchandani, Haresh. "Moves like Tagger: Meet the Austrian teen turning heads on tour." WTA, February 8, 2026. link

⁴ ORF Tirol. "Amstetten: Tagger startet als Major-Siegerin." ORF, August 4, 2025. link

⁵ VOL.AT. "First Bank Open: Tennis Superstar Sinner Returns to Vienna with Good Memories." VOL.AT, October 20, 2025. link