Co-Founder & Hitting Coach

Andre Marshall

Andre Marshall, outfielder and switch hitter, played for the Washington Huskies. Drafted by the Philadelphia Phillies, he went on to play minor league baseball for seven years.

Andre has been a hitting instructor for over 20 years and has had hundreds of high school players go on to both college and professional baseball. For 12 years, Andre coached at Mercer Island High School, where he won two state championships and coached outfield hitting and baserunning. 

Co-Founder & Pitching Coach

Sean White

Sean White is a former professional baseball player with a distinguished career both on and off the field. Growing up in Mercer Island, Washington, Sean showcased his pitching skills at Mercer Island High School. Opting for collegiate baseball over an immediate professional start, he attended the University of Washington.

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As a Husky from 2000 to 2003, he excelled as a starting pitcher, earning All-Pac-10 honorable mentions in both 2002 and 2003. Over four seasons with the Mariners (2007-2010), he maintained a win-loss record of 4-4 and an ERA of 4.16. His peak performance in 2009 included a 2.80 ERA across 52 outings, earning him the title of Mariners’ 2009 Unsung Hero by the Baseball Writers Association of America.

Manager of Baseball Operations & Infield Coach 

Dan Rickert

Dan Rickert graduated from Tyee High School in 1997. While at Tyee, Dan earned 1st team All-Seamount League honors as a middle infielder his Sophomore, Junior and Senior seasons. After graduating from Tyee, Dan went on to play JUCO baseball at Tacoma Community College (TCC). In his freshman year at TCC, Dan was named 1st team All-Western Division infielder as a 3rd baseman. As a sophomore, Dan was named 2nd team All-Western Division Infielder and 1st team All-NWAACC tournament team as a 2nd baseman.

Dan graduated from the University of Washington in 2002 with a degree in Sociology. After graduating, he played in the NABA and PSSBL baseball leagues for over 10 years. He has had a lifelong passion for baseball and has been coaching youth teams ever since he hung up his spikes as a player. 

Coach

Mason McAlister

Mason graduated from Yukon High School, Oklahoma, in 2014. He went on to pitch for Cowley College, Kansas, won a conference championship and played in the D1 JUCO World Series. 

In 2016, Mason transferred to Oklahoma Christian University and received an All-Conference Honorable Mention. For two years, Mason coached college baseball in the PIL and WCL leagues with the Redmond Dudes. In addition, he posted a career 3.77 ERA in three professional seasons in Independent Leagues (partner of MLB Leagues) and has 3+ years of experience training athletes to be more efficient in their movements and patterns. 
 

Coach

Colton Turner

Colton Turner, is the Head Velocity Trainer at Boost Baseball and the head coach of the 2025 New Level Boost 13u team. Colton specializes in biomechanics and overall efficiency, with a focus on helping athletes gain velocity while staying healthy and improving their pitching skills. 

With four years of college baseball experience, and occasionally playing in national men’s fastpitch tournaments, Colton’s passion for the game is evident in everything he does. Colton is committed not only to improving his players' physical performance, but also to enhancing their knowledge of the game and boosting their confidence both on and off the field. 

Coach

Spencer Shelton

Spencer attended Piedmont University, GA from 2006-2010. At Piedmont, he was a two-way player starter all four years; pitching was his primary role. From 2010-2011, Spencer played for the Chicago White Sox. After moving to Traverse City, MI, he played for the Traverse City Beach Bums. His next stops were Tennessee and his home state of Georgia. During his time there, Spencer taught hitting, pitching and fielding, as well as coaching travel teams. After moving to the Pacific Northwest in 2020, Spencer coached players at Linfield University, OR, and simultaneously earned his Certified Strength and Conditioning Specialist certification.

At Seattle University, Spencer worked with players using Trackman during scrimmages and home games, and shared the information and insights he had gleaned with the coaching staff. 

 
*Member of the Piedmont University Hall of Fame 

* Certified Strength and Conditioning Specialist certified 

Coach

Micah Yonamine

Micah graduated from Iolani School in Honolulu, Hawaii. In 2019, he was selected as the state Gatorade Player of the Year. Micah was drafted and signed out of high school by the Philadelphia Phillies, and he spent 4 years in their minor league system. 

Following his time with the Phillies, Micah continued his love for the game, playing in Independent Leagues for the Windy City Thunderbolts and Boise Hawks. In 2024, he set the Boise Hawks franchise record for the most hits in a single season. He also slugged 24 homeruns and drove in 96 RBIs that year. 

Micah specializes in catching and hitting development at Boost, blending both the physical and mental sides of the game. 

Coach

Stephen Englund

Stephen attended Bellevue High School from 2002-2006 where he was a 4-year Varsity starter on the baseball team, starting at shortstop as a 14-year-old freshman. He went on to earn Kingco League 1st Team All-Conference honors as a sophomore, junior, and a senior. He also received All-State honors as a junior, and as a senior he received Preseason All-American (Baseball America) honors. 

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During his senior year, Stephen signed a letter of intent to attend Washington State University on a full baseball scholarship. In the June 2006, he was then drafted in the 2nd round (70th overall) by the Washington Nationals MLB Draft. Stephen signed with the Nationals, foregoing WSU, and began his professional baseball career. He spent five seasons in the National’s minor league farm system, playing mostly center field. Stephen now enjoys fishing, golf, and teaching the game of baseball.