HomeWater PoloCoaches

Patriot Aquatics has a team of dedicated coaches for each squad, qualified for numerous finals.


Club Director and President
Head Coach - Age Group Water Polo, 16U & 18U Boys Water Polo

Duje Grubisic’s water polo career began in Croatia, where he played professional water polo, starting at the age of sixteen, and had the immense opportunity of being coached by some of the best water polo coaches in the world. Duje then landed a full water polo scholarship at Concordia University where he was voted most valuable player and earned all-American honors, three years in a row. After his undergraduate work, he was offered a graduate scholarship and while earning his Master’s Degree also landed a position as a graduate assistant coach for the men’s water polo team at Concordia. Additionally, Duje has been recognized as the captain of every water polo team he has been a part of.


Patriot Aquatics coaches are committed to excellence.


16U Boys Water Polo

Coach Matt Calhoun is from Visalia, CA in the central valley where he played water polo and swam for Mt. Whitney High School. After graduating he attended the College of the Sequoias for an associate’s degree, where he also swam, before transferring to UC Davis. At Davis he studied Psychology and played for the men’s club water polo team. Matt has been coaching water polo since the age of 19 beginning with the JV girls water polo team at Golden West High School. While in college he also coached the women’s club water polo B team and was president of the men’s club team for 2 years. Post-college Matt moved to Southern California and began assistant coaching for the Socal boy’s and girl’s 18U and 16U water polo teams.



10U Mixed and High School Water Polo

Coach Tijmen Egtberts was born and raised in The Netherlands. He started playing competitive water polo at the age of 8. His talent got recognized at Santa Rosa Junior College where he played for two years and was added to the coaching staff for one year as well. Tijmen continued his education at Concordia University where he played water polo for one year and was Senior Captain of the swim team his final year. He graduated in 2016 with a Bachelor’s degree in sports management and currently attends Concordia where he is working on a Masters of Science degree in Coaching and Athletic Administration with a focus on aquatics. As a coach, Tijmen has 8 years of experience and in 2017 he coached a 10U team that won the gold division at NJO’s.



10U Coed Coach, Specialty Coach

Coach Jeff has been with Patriot Water Polo since 2019 as an assistant 10u coach. From 1991-1995 Jeff played water polo with Canyon High School in Anaheim Hills. In 1994 he was selected to play with the USA Junior National team and then went on to win two back-to-back California State Championships with Golden West College. Since then, Jeff has continued to play water polo all over the country, even with the Navy Seals in Coronado. Jeff’s principal work is in physics, when he is not coaching or surfing, he can be found developing shot probability and data science models to help guide the 10u team to success.



12U Boys Water Polo

Skyler Chanove started playing water polo career at the age of 7 with team Vegas/ Henderson and continued his career with the SoCal water polo club. He went on to play for Foothill high school and later played for Orange Coast College men’s water polo team. Skyler is looking forward to help and teach the ways the amazing sport



High School Girls

Coach Kelsey Stumm was born in Long Beach, California. She was raised in Tustin California. She started playing water polo when she  was 14 years old. She played varsity water polo/ swim all 4 years at Tustin High School. Kelsey was the captain her senior year of high school. She went to Fullerton Junior College and played 2 years there. She was noticed for many achievements during her time at Fullerton Junior College including being an All American 2 years in a row. Then transferred to Concordia University, Irvine where she played for one year. Graduated in 2016 with a Bachelors in Liberal Studies, Child Development. After graduating Kelsey became an assistant coach at Concordia and still is today. She plans to finish her credential degree at Concordia to become a teacher.



Coach Sebastian was born and raised in Colombia, South America. Sebastian’s love for swimming began at a very young age when his mother taught him to swim. Sebastian began teaching learn to swim classes at 14 years old in Colombia. When he was 10 years old Sebastian earned a place on the State team in three different sports; european hand ball, volleyball, and water polo. When Sebastian was offered a spot on the Colombian National Team for water polo, he decided then to focus solely on aquatics. At age 15 Sebastian had the opportunity to represent Colombia’s master team, and was able to travel to countries such as Mexico and Brazil. He also swam for his high school, specializing in butterfly and freestyle events. He graduated from Salazar Y Herrera High School in 2003. Furthering his water polo career, at 17 Sebastian took the opportunity to play for Botafogo in Brazil for three months on their honor division.

At 19 years old Sebastian moved to the US and enrolled in American River College in Sacramento, CA. Here, he learned English and he continued studying the science behind swimming and attended the State Championships in 2007 and 2008. Sebastian transferred schools and moved to Irvine, CA. He was awarded a dual sports scholarship for water polo and swimming. He was named captain of the water polo team. In 2011 Sebastian competed in the Nationals and was part of the 200 freestyle relay that won 7th place. In 2012 Sebastian graduated from Vanguard University with a degree in business and administration with an emphasis in marketing.

Coach Sebastian has been a friendly, familiar face around Irvine pool for 10 years, His goal is to provide his groups with similar opportunities he was able to experience during the 20 plus years of his career.


16U Boys Water Polo

Bojan Hrlec was born and raised in Croatia, where he played for Kvarner and Primorje. He was a member of the Croatian Cadet/Junior Water Polo National Team (age 13-18). While studying at West Valley College, Bojan led the team to the state championship as the leading goal scorer and All American 2010/11 and 2011/12. While studying at the University of Califonia he was a member of the UCI Men’s Water Polo Team, NCAA Division 1 All American, and led UCI in scoring as a Junior with 63 goals. He graduated class of 2014. Bojan was 16U Assistant Coach, 12U, and 14U Head Coach from 2015 to 2017 at Del Mar Water Polo Club. As a Program Director at Del Mar Water Polo Club, he helped the club grow from 80 to 160 members, overlooked and coordinated all age groups and 10+ coaches, organized tournaments, year-long practice scheduling, as well as a club organization. He was also a 10U and 18U Head Coach and a club President until September 2018. Bojan was 12U and 18U Head Coach at La Jolla United Water Polo Club and assisted in strategically growing the club from 130 to 280 members in 1 year.



14U Boys Water Polo

Having experience at both the high school and collegiate club levels, Djippov will look to build the program. Prior to emigrating to the United States in 2015, Djippov was the assistant coach of Water Polo Club Cherno More-1948 in Varna, Bulgaria. A graduate from the University of Economics in Varna, Bulgaria, with a Bachelors Degree in Statistics and Econometrics along with a Masters Degree in Finance, Djippov was a member of the Bulgarian Senior and Junior National water polo teams and won the Bulgarian National Championship in both 2009 and 2010.


16U Boys Water Polo

Coach Gavin has many seasons of competitive water polo experience and training with SOCAL Water Polo including a national 16U gold medal in the Junior Olympics. His coaching experience includes coaching at his high school alma mater Foothill High School in Tustin.  He lead his team to win the DII CIF Title and he was awarded the honor of being named DII Southern Section CIF Player of the Year in 2015.  As a collegiate athlete, he played with the Pepperdine Waves. This is his third year of coaching. Two were official assistant coaching jobs and the other was back to back summers assisting.


12U/14U Girls Water Polo

Coach Hannah started playing water polo when she was 7 years old and played through SoCal from that age until she was 18. She also was a four-year varsity letter at Foothill High School, during her time at Foothill they made it to CIF finals two years in a row. She then was recruited to play at Azusa Pacific University. She did play all four years but due to the unfortunate COVID 19 shutdown her last two seasons of water polo were cut short but she did end her water polo career as a Division II All-American First Team in 2021. She graduated after four years with a bachelor’s degree in Criminal Justice. She has been coaching children in water polo skills and development since she was in high school and she has been coaching children on how to swim as well as proper swim techniques since she was around 13 years old. She has been a Patriot coach since she graduated college in 2021, she was also the assistant coach for the Beckman Varsity Women’s Team during the 2021 water polo season.


Patriot Aquatics coaches are committed to excellence.


High School


Age Group Swim


14U Boys Water Polo

Coach Patrik is a student-athlete at Concordia University, majoring in Business Administration, the major emphasis in Finance and Healthcare Management. He is a dual-sport athlete both swimming and playing water polo for Concordia. He is a DII all American, had the team-high scores and assists during the 2019 season. Patrik is also from Hungary where he learned to love the water. In 2017 his team placed second at the Hungarian U18 National Championship. He was then recruited to Concordia University where he made the WWPA conference all-freshman team. Patrik has been coaching in Southern California since 2017 and has coached 12u, 16u, and 18u Boys. He is currently swimming and playing water polo for Concordia while attending school and is the Patriot 18u Boys coach.



14U Water Polo

Started playing water polo at age 7 in Vilnius, Lithuania. Played for the national team in multiple age groups, won Nordic Championship 3 times, and was selected most valuable player in all three tournaments. With the club team Baltic Amadeus, he won the Lithuanian Championship 5 years in a row. Started playing for Lithuanian men’s national team at age 15 and still plays to this day. In 2017 was selected U18 athlete of the year. Currently is playing at Concordia University Irvine. This year broke the record of goals scored in single-season (102). Senior who is majoring in Mathematics and Computer Science.



High School Girls

Robert Amakasu’s water polo roots began when he started swimming at the age of 6. He swam all the way through school until high school where he followed the path of his older brothers and started playing water polo. He played varsity water polo and swimming at Bonita High School.

After graduating from high school, Robert became an assistant coach at Claremont High School for 2 years. Later he served as an assistant coach to head coach and brother, Mark Amakasu at Bonita High School. The two helped Bonita High School win the CIF championship in 2005. Robert also has a coach’s license for USA Basketball. He has been coaching basketball for over 4 years to boys and girls of the ages 6 to 12.

Robert has since married and has 3 children that are involved in many different sports. He is a resident of Irvine and is constantly involved in the athletic community and would like to return to the water polo community specifically.



12/14U Girls Water Polo

Coach Manon was born in Rambouillet, France and moved to the United States at the age of 4. Since being in the States, she has lived in the Tustin and Irvine areas. She attended Beckman High School and recently graduated in 2019. While attending Beckman, she swam Junior Varsity all four years of her high school career. She also played JV water polo her junior year and Varsity her senior year. Manon was co-captain of her water polo team senior year and contributed to their teams first Pacific Coast League win in Beckman history. Since graduating, Manon has been attending Santiago Canyon College with a major in mathematics, with hopes of transferring to the University of California, Irvine in two years. During her time at Patriot Aquatics, Manon has Head Coached age group swim and assisted in 12/14U Girls Water Polo and 14U Boys Water Polo. She is currently the Head Coach of the 12/14U Girls Water Polo team. On her free time, Manon likes to go to the beach, create art, and read.


He started playing water polo at the age of 10 and continued playing for almost 11 years. Garrett has also known Coach Duje for the better part of 10 years now as well. His experience ranges from club-level competition up to the international competition. Garrett played for Orange County Water Polo Club for much of his youth with numerous Top 5 finishes at JO’s. Then transitioned to Long Beach State for his collegiate career where he played for 2.5 years until his time was cut short due to a severe shoulder injury. He also has experience on the international level representing his mother’s home country of Ecuador in numerous competitions around South America culminating in a trip to the 2015 Pan American Games in Toronto, Canada.

After his playing days were over he transitioned to coaching where he coached 12U and 18U teams for OCPWC and for San Juan Hills High School where he was the Assistant Head Coach for two seasons.

He currently works as a financial advisor for his family’s financial planning firm however coaching is still a passion of his and something that he enjoys greatly as it allows him to give back to the coaches who helped him on his journey as well as educate the younger generations of athletes. Garrett is very thankful for Coach Duje giving me this opportunity and he is excited to begin working with the goalies.


Mia is a senior at Beckman High School. She started swimming when she was five years old. She started playing water polo soon after. She moved to California and joined SOCAL water polo club and SOCAL aquatics. She participated in several JO’s and swim meets while playing club. During high school she played on the varsity water polo team for all four years and swim team for three years. Her favorite events are the 50 free and 100 free. She loves teaching kids the fundamentals of swimming and having fun while doing it.



Patriot Aquatics is committed to creating a highly competitive athletic environment in an atmosphere instilled with high ethical values.


Don't miss our latest news, tournaments, and swimming updates.

    I agree with Patriot Aquatics Privacy Policy.

    Mailing Address: 325 Esplanade, Irvine, CA 92612
    Practice Location – Beckman High School: 3588 Bryan Avenue, Irvine, CA 92602 | Email: admin@patriotaquatics.org

    May the Avensys be with you.

    Privacy Policy | Terms Of Service
    Copyright © 2020. Patriot Aquatics. All rights reserved.