With IMG Academy backing, Wakana Sonobe kicks off pro career at home in Osaka

Coach Margie Zesinger called Wakana Sonobe “The Silent Killer.”

“She’s one of the most competitive individuals you could possibly meet,” IMG Academy’s Head of Female Tennis told me. “She’s still very shy and introverted, but when you see the talking she does with her racquet, suddenly she speaks very loudly.”

🖥️📲 Stream highlights from Sonobe's match vs. Naomi Osaka on the Tennis Channel App!

The latest IMG Academy wunderkind, who announced her decision to turn pro last week, has been making noise from the start of the 2025 season. At 17 years old, she stormed to the junior Australian Open title, losing just one game in the final. By May, she stood atop the ITF Junior rankings.

A big-hitting lefty, Sonobe first served notice last summer when she finished runner-up at the US Open girl’s tournament, hearkening the arrival of a new wave of Japanese superstars.

Like former world No. 4 Kei Nishikori before her, Sonobe was a recipient of the Masaaki Morita Tennis Fund, which provides an IMG Academy scholarship to the most talented teenagers in the country.

“During her career at the IMG Academy, we trained her in our program,” explained Zesinger, who has been with the IMG Academy since 2003. “We then had a Morita Fund coach, Ryuji Hirooka, who traveled with her. He was hired under IMG to be the Morita representative. He also overaw Rei Sakamoto and the other players part of Morita project. Right now, what we’re doing is building out a team for her under the IMG Academy umbrella, so we’ll be sending a full-time travel coach from our academy with her.

“Molding it all together is super important because so many juniors or pros just go off previous coaching and during this kind of transition, it’s important to have coaches like Ryuji and Jorge Gonzalez, who worked with her a lot here, as well as myself, to really help her through that transition as she gets to know her travel coach.”

Sonobe began that transition not long after lifting the junior title in Melbourne. The very next week, she made her WTA main-draw debut as a qualifier at the Abu Dhabi Open. Two months later, she won her first W100 ITF Pro Circuit title in Gifu, Japan, ultimately rising to just outside the Top 250 by this fall.

In between, Sonobe returns in the IMG Academy dorms, where she’s lived and trained since she was 13 years old.

It’s very easy to stress out as you make a transition when all it might take is one match or one tournament before you completely skyrocket. She’ll have one of those moments. IMG Coach Margie Zesinger on Wakana Sonobe

“When you get to a level from where you’re always winning in juniors to having a lot more losses, I think that can challenge that transition period,” said Zesinger. “One of the bigger things for Wakana is that her turning pro is a big story in Japan. So, she probably feels a lot of weight and pressure to uphold the standard of what people think she can maintain. I think there’s a little extra pressure during this period she will probably put on herself.

“But the cool part is that she has so much in line. She’s so professional, and she has so much support already in place, so during challenging times, she has all the resources to help her through that.”

Zesinger credits IMG’s holistic approach to junior development as essential to guide international players through the U.S. culture shock and develop the social skills necessary to navigate the professional tour.

“They need to be able to open up and communicate for themselves,” said Zesinger. “Wakana comes from such a respectful, loyal culture, but at some point, to be a professional tennis player, players all need to be able to run their own companies because they’re the CEOs of their teams. We were very intentional from when we brought Wakana here at a young age. We had many Japanese girls here already to help Wakana, like Sayaka Ishii, who is doing very well on the WTA Tour now. Ena Koike was here, too. Rei [Sakamoto] was here, as well. So, we have a little bit of Japanese culture already here. They feel like they have a family here.

“The culture shock does take time, but she would take roller coaster trips with us to Busch Gardens, dressing up in Halloween costumes. This is a player whose career could have been so one-dimensional, but she’s been able to experience the fun, social elements of tennis.”

The fun continued for Sonobe at the Kinoshita Group Japan Open, where she came face-to-face with countrywoman Naomi Osaka. After a quick first set, Sonobe dug in and acquitted herself well against the former world No. 1 for a 6-0, 6-4 scoreline.

“Coaches are very fast to jump and say a player needs to be more aggressive or consistent,” said Zesinger. “We learned from Nick Bollettieri to take a step back and really see before we speak. She is a super aggressive player, and we’re working on perhaps not pulling the trigger too early on her strokes and being slightly more patience. When I say ‘slightly,’ we don’t want to take away what’s worked. What has made her so great is her relentless depth and the power on her ball, the weight of her ball.

“A lot of it at this point is getting her to have belief and keep her relaxed so she can enjoy this part of her career. It’s very easy to stress out as you make a transition when all it might take is one match or one tournament before you completely skyrocket. She’ll have one of those moments. So, it’s just about preserving her through those stressful moments when she may not be winning as much and making she we continue to work on her game without changing too much what she has.”

For her part, Sonobe has charmingly more humble goals, telling coaches her dream of becoming a Top 30 player.

“We were like, ‘Wakana, we want you to say No. 1!’” joked Zesinger.

In the meantime, Sonobe targets Grand Slam qualifying as her next big milestone. With prodigious talent and strong support at home and abroad, look for the Silent Killer to make even more noise in 2026.