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Surina DeBeer

SURINA DE BEER was introduced to the sport of tennis at age 6. After a successful junior career in which she reached the #1 ranking in the world under 16 and winning two Junior US Open Doubles titles, she turned pro at the age of 18. De Beer played in all four Grand Slams, Tournaments, and reached the 3rd round of Wimbledon in Singles in 1998. She also reached a career high ranking of 109 in Singles and 49 in Doubles on the WTA (Professional Women Tennis Association Tour).

Throughout her years of playing, she won a total of 46 career ITF women on the WTA (Professional Women Tennis Tour). As a junior player, she helped win the World Youth Cup for South Africa as the #1 player. Originally from South Africa, it was the first time in history that an African country won this title. Surina was awarded 2 South African Victor Sports Awards in 1995 (Most Promising Newcomer and Best Team). She played multiple times in the WTT (World Team Tennis Tournament) De Beer represented South Africa twice in Fed Cup.

Due to injuries, she retired in 2011 from professional tennis. De Beer has been teaching tennis for 14+ years and has worked with hundreds of adults and children. She is Lawn Tennis Association Certified(LTA), and a member of the Professional Tennis Registry(PTR). De Beer primarily coaches junior players, ages 7-13 years, which has become her specialty. She has traveled with junior players to Junior ITF Tournaments, and coached the current Top 10 WTA player, Johanna Konta, to success in her first ITF junior tournament when Konta was 15.

Surina has known Reynaldo and Hanna since 2014 when she happened to be running errands and walked into Zalles Racquet Sports. She ended up speaking with Reynaldo for over an hour that day! During the next few years, Reynaldo and Surina collaborated to present “Tennis Experts are in Town,” which were USANA/tennis injury prevention events in Foster City. That was only the start of Reynaldo becoming a friend and valued mentor in her tennis journey. Surina’s partnership with Bérénice and Icuemotion in 2017 created this opportunity to bring technology to the Foster City tennis community. Becoming a co-owner in the store is a dream come true and she hopes she can continue the Zalles legacy.



 
SURINA DE BEER was introduced to the sport of tennis at age 6. After a successful junior career in which she reached the #1 ranking in the world under 16, and winning two Junior US Open Doubles titles, she turned pro at the age of 18. De Beer played, in all, four Grand Slams, Tournaments, and reached the 3rd round of Wimbledon in Singles in 1998. She also reached a career high ranking of 109 in Singles and 49 in Doubles on the WTA (Professional Women Tennis Association Tour).

Throughout her years of playing, she won a total of 46 career ITF women on the WTA (Professional Women Tennis Tour). As a junior player, she helped win the World Youth Cup for South Africa as the #1 player. Originally from South Africa, it was the first time in history that an African country won this title. Surina was awarded 2 South African Victor Sports Awards in 1995 (Most Promising Newcomer and Best Team). She played multiple times in the WTT (World Team Tennis Tournament) De Beer represented South Africa twice in Fed Cup.

Due to injuries, she retired in 2011 from professional tennis. De Beer has been teaching tennis for 14+ years and has worked with hundreds of adults and children. She is Lawn Tennis Association Certified(LTA), and a member of the Professional Tennis Registry(PTR). De Beer primarily coaches junior players, ages 7-13 years, which has become her specialty. She has traveled with junior players to Junior ITF Tournaments, and coached the current Top 10 WTA player, Johanna Konta, to success in her first ITF junior tournament when Konta was 15.

Surina has known Reynaldo and Hanna since 2014 when she happened to be running errands and walked into Zalles Racquet Sports. She ended up speaking with Reynaldo for over an hour that day! During the next few years, Reynaldo and Surina collaborated to present “Tennis Experts are in Town,” which were USANA/tennis injury prevention events in Foster City. That was only the start of Reynaldo becoming a friend and valued mentor in her tennis journey. Surina’s partnership with Bérénice and Icuemotion in 2017 created this opportunity to bring technology to the Foster City tennis community. Becoming a co-owner in the store is a dream come true and she hopes she can continue the Zalles legacy.


Bérénice Mettler


Bérénice Mettler has played tennis recreationally since her childhood in Switzerland, where she developed a lifelong fascination with human movement and the challenges of using technology to reproduce those skills. In 1997 she came to the US to pursue her PhD in Robotics at Carnegie Mellon University, and after completing post-doctoral research at Massachusetts Institute of Technology, she started the Interactive Guidance and Control Lab at the University of Minnesota where she was a tenured faculty from 2006-2017. Her research there focused simultaneously on autonomous flight and gaining insight into how human pilots acquire their unique capabilities. 

Bérénice first got to know the Bay Area over the course of several summers, working at NASA Ames in Mountain View, in connection with her PhD program. In 2011, in addition to her aerospace research, she conducted some of the earliest studies incorporating motion sensors onto a tennis racket. Shortly after, she launched iCueMotion(iCueMotion.com) with the goal of building technology to help people learn movement skills more efficiently, combining wearable sensors, miniaturized computers, and machine learning. In 2016 she went on academic sabbatical to focus on the company, and in 2018 she and her team delivered the initial prototype of the CueMate tennis training system(https://tennis.cuemate.com/

Bérénice met Surina DeBeer through common friends, and for the past couple of years they have partnered on integrating CueMate with tennis coaching. In 2020 she connected with Renaldo and Hanna Zalles, which led to become a co-owner of Zalles Racquet Sports. She is delighted to be part of Foster City’s thriving tennis community, the ideal context for enjoying her favorite sport while testing and launching CueMate’s training technology. 
Due to injuries, she retired in 2011 from professional tennis. De Beer has been teaching tennis for 14+ years and has worked with hundreds of adults and children. She is Lawn Tennis Association Certified(LTA), and a member of the Professional Tennis Registry(PTR). De Beer primarily coaches junior players, ages 7-13 years, which has become her specialty. She has traveled with junior players to Junior ITF Tournaments, and coached the current Top 10 WTA player, Johanna Konta, to success in her first ITF junior tournament when Konta was 15.

In January 2017, Bérénice’s research was honored by President Obama’s White House Office of Science and Technology with the Presidential Award for Early Career in Science and Engineering(PECASE).

 
Vince Warren

Vince has been at Zalles since 2006 and began his journey stringing rackets back in 1994. We estimate he has strung over 70,000 rackets! Seldom will you find a stringer with this amount of stringing experience and knowledge about the strings on the market. In addition, Vince has expertise to help you find the right racquet as well as he stays up to date on the latest technology. He is always happy to help guide you to find optimal tension according your playing style, preferences, and even the current weather. Vince is also known as the heartbeat of the store!

 
Will Devine

Will has been stringing for Zalles Racquet Sports since 2005. He has strung in the ATP/ WTA tours since 2006. Will has worked many local Tour events including the SAP 2006-2013 , BANK OF THE West /Mubadala 2006 until now and ATP 1000 western and Southern. However the biggest of them all is stringing at the US Open 2020 where he strung over 400 racquets! He began in 1984 and estimates stringing 90,000 rackets so far throughout his stringing journey!

He has been the official stringer for the Stanford Women’s Tennis Team since 2013, who can boast winning 3 national championship titles during this time to add to Will’s impressive stringing resume. His skill, experience and knowledge is simply one of the best in this field!



 
Ethan Smith

Ethan walked into the store when he was only 5 years old and has been playing tennis since then! Ethan and Thomas grew up together playing doubles as juniors as consistent Top 10 Nor Cal Junior players.

Ethan has been stringing and helping customers at Zalles since 2016.  He earned a scholarship to play Division 2 College tennis at Azusa Pacific University.  He won National level 2 tournaments as a junior and is studying systems engineering.


Thomas Reznik 

Thomas started his tennis journey walking into the Zalles Racquets Sports store at 6 years old. Vince started stringing his rackets for him and advising him on racquets as he progressed.  Thomas gave a lot of credit to Vince’s stringing skill that had him play consistently as a Top 10 Nor Cal Junior Player.

Thomas and Ethan grew up together playing doubles since they were 12 years old!  His 14 years of tennis experience got him a scholarship at the University of Redlands in Southern California where he currently studies computer science. Since the age of 16, Thomas has been part of our Zalles Staff family part-time between school.  Did we mention Vince taught him how to string?

Sarah Ehler

Sarah has a wide variety of experience in sports retail, management, exercise science and rehabilitation.  She is a Physical Therapy Assistant and recently relocated from Austin, Texas.  Sarah is a recreational tennis player, an avid runner, and outdoor enthusiast.  She is new to Zalles and enjoys helping with inventory and merchandising.  She is eager to help you find what you are looking for at Zalles Racquet Sports! 

 
Andres Godoy

Andres is a tennis enthusiast and has played in USTA events.  Working at Zalles while being a full-time high school student says a lot about his dedication to serve the tennis community here in Foster City.  He is a fast learner as he absorbs the expertise and experience from all of our long standing Zalles family staff members. 

 
Stephen Lum

Stephen has been stringing rackets for 54 years at events such as The Bank of the West WTA tournament.  He has even strung for Monica Seles!  

Stephen has strung roughly 35,000 rackets to add to his experience.  Stephen also loves playing pickle ball!. 

 
Leila Russell

Leila worked for Zalles from 2001-2014 as their store manager ("Jill of all trades").  Leila remains close friends with Reynaldo and Hannah and has a personal passion for tennis.  In 2018, she completed her bachelor's degree in accounting and we are extremely lucky to have her experience and fun-loving attitude as she keeps our books (and keeps us in line) to this day!  You may not run into her in the store, but she is very much a part of Zalles.  Fun fact: Many assumed she was Reynaldo and Hannah's daughter and she didn't feel the need to correct them.



 
Reynaldo and Hanna Zalles 

Our original founders of Zalles Racquet Sports, which they built and served the Foster city and surrounding areas for the past 30 years.  The valuable service they provided to the Tennis community is a legacy that lives on for many people who still walk through the doors today. 
They sold their beloved store to Surina and Berenice in September 2020.
Reynaldo is an official member of the Foster City Hall of Fame.  

We wish Reynaldo and Hanna the best in their retirement and thank them for remaining our advisors and store Grandparents to this day.