Professional Tennis Registry (PTR) on Sunday announced the passing of its founder, former chairman and president, Dennis Van der Meer. He was 86.

“Dennis was a mentor, friend, educator and advocate for countless tennis coaches around the world,” said Dan Santourm, PTR CEO. “Dennis embodied the PTR manta—he truly Made a World of Difference.”

Indeed, Van der Meer dedicated his life to tennis, more importantly to coaching. He was the teacher among teachers, constantly seeking information on biomechanics, methodology and techniques. As an innovator in the field of tennis education, Van der Meer believed in sharing knowledge.

During the early stages of PTR, known then as USPTR, Van der Meer found that only limited educational materials existed for tennis teaching professionals. So, he set about to provide a series of handbooks and manuals by assembling the finest educators to write on their areas of expertise. To compliment the vast collection of written materials, he produced a large number of videos illustrating teaching techniques. Since the mid-1970s, hundreds of thousands worldwide have learned to teach tennis in ways developed by Van der Meer.

“The industry lost a legend this week,” said Karl Hale, PTR board president. “Dennis did more for the growth of tennis and coaching education than any one individual in the history of the game.”

Van der Meer also touched countless lives through his Standard Method of teaching, World Class Academy and TennisUniversity. The boy who grew up traveling through African villages with missionary parents became a coach so renowned that Billie Jean King, Margaret Court, Amanda Coetzer and others, sought his expertise.

Although tennis lost an icon, he will live on in generations of tennis coaches and players to come. Known for his uncanny ability to remember the name of everyone he met, his name will live on in our hearts. Van der Meer’s legacy will live on forever.