Developing a Junior Slam Champion — Mark Carruthers

Summary

Mark Carruthers, a New Zealand-born coach based in Austria, tells the story of discovering and developing Lily Tagger, the 2025 Roland Garros junior girls champion, from age 9. The central narrative is the controversial decision to switch Lily from a two-handed to a one-handed backhand — a choice driven by the player herself, supported by Carruthers and her parents, and opposed by the Austrian coaching establishment. The episode is a masterclass in player-led development, long-term thinking, parental trust, and the courage to resist conventional wisdom. Lily won the final 6-2, 6-0.

Guest Background

Mark Carruthers grew up in Auckland, New Zealand, where he was a promising junior before injuries ended his playing career around age 16. He earned a journalism degree, then fell back into tennis coaching. He coached in Canada, Hong Kong, and Singapore before following his wife to Austria, where he now runs a small coaching operation near Kitzbuhel. He connected with Lily Tagger’s family when Lily was 9 years old, after a girl in his training group invited Lily to practice.

Key Topics

Discovering Lily Tagger

• Noticed within two hours that 9-year-old Lily wanted to come to the net, sliced naturally, volleyed well, and had no interest in developing her two-handed backhand.
• Told Lily’s mother: “You realize your daughter should be hitting a one-handed backhand, right?”
• Lily was a huge Federer fan and always wanted to play with one hand.
• Carruthers: “She had something you can’t teach. Very tall, great athlete, trying to play in a way where you’re watching her and it was completely nuts at the time.”

The One-Handed Backhand Decision

• Lily decided herself after winning a tournament with two hands: “I’m gonna try and start playing with one hand.”
• Carruthers encouraged and “manipulated” (his word) the situation by consistently noting she should try one hand, but the final decision was Lily’s.
• The first intensive session was 4 hours straight with a 10-year-old, just on the one-handed backhand. Carruthers was convinced immediately.
• “Massive amounts of blowback in Austria” from the coaching community. “The whole coaching community basically thought I was completely out of my mind.”
• Carruthers’ conviction grew with opposition: “The more people challenged it, the more convinced I became.”

The Development Process

• Year one was rough: Lily lost to everyone. But Carruthers and her parents committed to treating it as a “gap year.”
• “All this kid needs is time. So send her back out there, let her play, let her compete.”
• Lily’s family structure was a massive advantage: older sister Emma, older brother, and parents who all played tennis. She had hitting partners at home constantly.
• By end of year one, the one-hander was “starting to piece together.” By year two, she was putting it into matches with confidence.
• Carruthers drove 90 minutes each way for sessions; the family drove to him twice a week.
• Communication with parents was constant and open. They understood under-10/under-12 results were irrelevant.

Coaching Philosophy

• “It’s the kid’s tennis. It’s not the coach’s tennis.”
• Used historical examples to counter critics: Sabatini, Graf (slice), Mauresmo, Henin, Schiavone — all had excellent one-handed backhands.
• Embraced Craig O’Shannessy’s data on net play effectiveness to encourage Lily’s attacking instincts.
• “No great player’s ever been scared on a big point to go for their shot. We’re going to do this now.”
• Nick Bollettieri’s approach with Boris Becker: not saying anything until he had something that would add value. Carruthers applied this restraint.
• “If you want to climb the mountain, you’re going to have to take some risks along the way.”

Transition Away from Carruthers

• Distance (90 minutes) became unsustainable as Lily needed more intensive daily training around age 12.
• Carruthers recommended French or Italian coaches who would “let her be herself” and not try to put her in a box.
• Lily spent time in South Tyrol (Sinner’s circle — Max Satori, formerly with Andrea Seppi) before connecting with Francesca Schiavone.
• Carruthers’ biggest fear was that a “German, Swiss, or Austrian type coach who would be very precise” would suppress her creativity.

Lily’s Current Game

• Won Roland Garros junior final 6-2, 6-0.
• One-handed backhand, serve and volley, creative variety, all-court game.
• “You have to adjust to a very confident natural shot maker at the top of her game.”
• The Italian coaching team did excellent work on her mental composure, which was an area Carruthers acknowledged needed development.

Actionable Advice for Families

1. Listen to your child’s instincts about how they want to play — even at ages 9-10, players often know what feels natural to them. Don’t force them into a pre-packaged template.
2. Give development time — the one-handed backhand took a full year of losing before it started clicking. Under-10 and under-12 results are meaningless in the big picture.
3. Coach-parent communication is everything — Carruthers spent extensive time after every session updating Lily’s parents. Alignment between coach, player, and parents made the controversial decision sustainable.
4. Don’t fear being different — “If everyone’s going to nail two handers cross court and play flat and not come to the net, why don’t you be the one person that everyone else has to adjust to?”
5. Know when to transition coaches — Carruthers recognized his limitations (distance, solo operation) and recommended the next step. A great early developmental coach doesn’t have to be the coach for life.

INTENNSE Relevance

• Player-centered development: Carruthers’ philosophy of letting the player lead aligns with INTENNSE’s approach to building a league around what players and families actually need, not what tradition dictates.
• Resistance to conventional wisdom: The Austrian coaching establishment’s opposition to Lily’s one-hander mirrors the tennis establishment’s resistance to INTENNSE’s format innovations. Both succeeded by ignoring conventional criticism and focusing on results.
• Junior development patience: The story validates INTENNSE’s message that the current junior system’s obsession with early results (rankings, ratings) is counterproductive to long-term player development.
• European development model: Understanding how top European juniors are developed (small coaching operations, family involvement, gradual progression to elite academies) provides context for how INTENNSE might position its junior pathway internationally.

Notable Quotes

“People just forget, especially coaches, that it’s the kid’s tennis. It’s not the coach’s tennis.” — Mark Carruthers

“The more people who say this is a bad idea, they haven’t looked at the history of tennis, and they’re just taking convenient snapshots to fit a well-known narrative around girls’ tennis.” — Mark Carruthers

“If you want to climb the mountain, you’re going to have to take some risks along the way. And I thought the sooner you do it… don’t put these things off.” — Mark Carruthers