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Mark McGwire

Advisory Panel
Mark McGwire’s success on the baseball field is well-documented. He’s No. 11 on the all-time list with 583 home runs in Major League Baseball. He was American League Rookie of the Year in 1987, a 12-time All-Star, Gold Glove Award winner and two-time World Series Champion. He also had successful stints in the dugout as a hitting and bench coach for the St. Louis Cardinals, the Los Angeles Dodgers and the San Diego Padre. Now, Big Mac is bringing his expertise and knowledge to the TRUE Diamond Science Advisory Panel. As a father of five, Mark is passionate about the youth athlete and helping them progress their skill sets. He will be a vital member of our team as we work to disrupt the youth baseball landscape.

Édgar Rentería

Advisory Panel
Edgar Renteria brings a wealth of baseball and hitting knowledge to the TRUE Sports Advisory Panel. The five-time Major League Baseball All-Star, three-time Silver Slugger Award winner and 2010 World Series MVP has a full trophy case to showcase his hitting abilities, but his individual awards aren’t his only asset, his ability to transfer knowledge to young athletes is key. Edgar has always had a passion for the development of amateur athletes. In 1998, with his brother Edinson, he created Team Renteria to help Colombian baseball by giving professional instruction at youth clinics for amateurs and aspiring professionals. He has continued that same dedication to the amateur athlete throughout his career and will be a vital part of the TRUE Diamond Science team.

Eric Byrnes

Advisory Panel
Eric Byrnes brings passion and hustle to every endeavor. The former Major League Baseball outfielder turned baseball analyst hasn’t stopped moving since his 10-year playing career ended. He has worked for ESPN and FOX, hosted his own TV show on FSN Arizona and held the mic on his weekly radio show on SiriusXM. He’s completed 11 Ironman triathlons, and, in 2019, he set a speed golf record with 420 holes played in a 24-hour span. Eric is also an avid supporter of the Pat Tillman Foundation, Challenged Athletes Foundation and Fit Kids as well as a father of three. His willingness to keep pushing along with his constant energy will be a tremendous asset as a member of the TRUE Diamond Science Advisory Panel.

Ryan Fuller

Advisory Panel
Ryan Fuller is the owner and lead instructor at Fuller Hitting. Fuller is a former NCAA Division I athlete who was an All-Big East performer and team captain at the University of Connecticut (UCONN). After his UCONN career was complete, Ryan signed a contract with the Arizona Diamondbacks and played professionally for a few seasons. Once his professional baseball career came to a close, Ryan served as an assistant coach at Quinnipiac University and also coached high school baseball in Connecticut. His main objective is to help educate hitters and cultivate their confidence. Fuller consistently works hard as a hitting coach in Connecticut and an online remote training coach. Now, he is bringing his experience and knowledge of hitting and digital platforms to the TRUE Diamond Science Advisory Panel.

Dan Keller

Advisory Panel
Dan Keller’s success on the field as an athlete, his time on the bench as a coach and his view from the stands as a parent are the perfect combination for a TRUE Diamond Science Advisor. Keller, a former UCLA baseball player and now as CEO of Dugout Captain, has been coaching teams, running camps and speaking at seminars and clinics for 16 years. Having worked with over 10,000 youth baseball coaches, he’s made it vividly clear that practice-planning is the biggest obstacle to their success. Dan is a passionate father, coach and instructor to thousands of parents and coaches. He will be a valued member of the TRUE Diamond Science advisory board.

Ariel Polanco

Advisory Panel
Ariel Polanco is a former Central Intercollegiate Athletic Association (CIAA) Player of the Year and current professional baseball instructor. Ariel draws on his experience from collegiate baseball and the Dominican Summer League to educate youth athletes. He brings an advanced level of hitting knowledge and social media marketing experience to the TRUE Diamond Science team. Currently Ariel serves as a hitting and fielding instructor in Atlanta, Georgia, and provides online instruction through his platform

Dave Coggin

Advisory Panel
As a former Major League Baseball first-round pick and the current owner of Performance Fitness for Athletes, Dave Coggin provides a significant presence for TRUE Diamond Science within Southern California. His facility, one of the country’s premier baseball training sites, is located in Upland, California. He is known within the baseball community for his ability to help players advance their skills from youth baseball to collegiate and professional levels. His methods have been so effective that MLB teams are now hiring him to consult their coaching staff on his techniques. Dave is a passionate husband, father, business owner and now Advisory Panel member for TRUE. The baseball, business and marketing experience is a great addition to the Diamond Science team.

Tim Gibbons

Advisory Panel
Tim Gibbons is a captivating teacher when it comes to the art of hitting. He has a new school approach to the swing but also pulls influences from the past like Ted Williams. Tim is engaged and active online with a quality following around @linedrivepro. He currently works out of Long Island, New York, and teaches his methods of hitting from the youth to professional level. Tim brings great value to the TRUE Diamond Science team by providing his methods of hitting to TRUE bat fitting experiences.

Scott Brown

Advisory Panel
Scott Brown brings his knowledge of baseball, softball and retail business to the TRUE DIamond Science Advisory Panel. Scott was a successful softball player winning the 2001 USSSA “AA” World Series while being named the Most Valuable Player. Currently he lives in Minnesota with his family and is the owner of P5 apparel athletic wear. We are excited to be able to pull from Scott’s vast experience of the game and his knowledge of the retail business.

Matt Walbeck

Advisory Panel
Matt Walbeck was selected by the Chicago Cubs 192nd overall (eighth round) in the 1987 draft. Walbeck made his Major League debut on April 7, 1993 at the age of 23 against the Atlanta Braves. Matt Walbecks last career final hit, a two-run home run, came on August 8, 2003 off pitcher Kenny Rogers.

November of 2007, Walbeck was hired by the Texas Rangers to be their third base coach. In addition to those duties, Walbeck also handled the catchers and coordinated spring training activities. December of 2008, Walbeck landed a role with managing the Eastern League Altoona Curve. In 2010, Walbeck's helped win the EL championship, and he was again named EL Manager of the Year.

Matt is a proud father of 3 and passionate coach & business owner of Walbeck Baseball Academy. The academy successfully runs hitting, pitching, training and travel baseball programs. Matt’s playing, coaching and business experience is a huge value to the TRUE Team & is a great addition to the TRUE Advisory Panel.

Bill Phillips

Advisory Panel
Bill Phillips brings his understanding and knowledge of retail and sales to the TRUE Diamond Science Advisory Panel. As a successful entrepreneur, he has had many wins in retail business operations. Currently Bill owns and operates “Play It Again Sports” in Orange County, California. The TRUE Diamond Science team is excited to have him on the Advisory Panel to draw on his retail expertise and point of sale knowledge.