Who We Are at Beckman High School Boys Water Polo

Duje Grubisic is a visionary leader in the world of water polo and aquatics. Born and raised in Croatia, Duje began his professional water polo career at the age of sixteen. His early experiences in one of Europe’s water polo powerhouses provided him with a solid foundation, which he later built upon during his collegiate career at Concordia University in the United States. Earning a full athletic scholarship, Duje was a three-time All-American and also earned Academic All-American honors during his time at Concordia University. His leadership qualities extended beyond the pool, culminating in a scholarship for his master’s degree and a role as a graduate assistant coach for Concordia’s men’s water polo team.Duje’s coaching career is marked by remarkable success and accolades. As the founder, President, and CEO of Patriot Aquatics and head coach for both the 14U girls team and Beckman High School, he transformed the club from its humble beginnings into a nationally recognized powerhouse, now boasting over 300 athletes. His ability to develop both athletes and coaching staff has resulted in an organization known for both its competitiveness and its supportive, family-like atmosphere.Throughout his career, Duje has personally achieved numerous prestigious titles, including:

• ⁠2nd place in the 14U boys Platinum Division at the Junior Olympics
• 3rd place in the 10U coed Platinum Division at the Junior Olympics
• 10U boys and girls national champions
• 12U girls national champions 
• 1⁠4U girls Cal Cup champions 
• 12U and 14U girls Futures champions
• 18U boys Futures League Division 2 champions

In recognition of his dedication and skill, Duje has received several prestigious awards, including being named the Orange County Athletic Directors Association Coach of Character* in 2020 and OC Register Coach of the Year in 2023. His leadership guided both boys’ and girls’ teams to the semifinals of CIF Division 2, marking a historic achievement for the teams under his care.Duje's educational background is as impressive as his coaching career. He holds a Bachelor of Arts in Business with a concentration in Accounting and Finance from Concordia University Irvine, a Master of Business Administration (MBA), a Master of Coaching and Athletic Administration, and a Master of Coaching and Exercise Science all from Concordia University Irvine. This robust academic foundation complements his professional experience, allowing him to manage and lead Patriot Aquatics with exceptional business acumen and coaching expertise.Duje’s athletes have gone on to play for prestigious teams such as Stanford, UCI, USC, Berkeley, Harvard, MIT, UCSD, UC Merced, Concordia, LMU, Pomona Pitzer, Redlands, and Claremont. Under his guidance, his players have also won national championships in various divisions.With his passion for developing well-rounded athletes, Duje is committed to nurturing talent both in and out of the pool. His approach to coaching emphasizes not only athletic excellence but also personal growth, character, and academic success. His athletes have gone on to compete at the highest levels, earning scholarships and national team placements.Duje’s influence extends beyond the sport, as he continues to mentor young athletes, inspire his coaching peers, and lead Patriot Aquatics with an unwavering commitment to excellence and integrity. 

• 2018/2019 CIF SS Open
• Division Champion 2018/2019 CIF SS first team
• 2019 Futures Superfinals D1 MVP
• UCLA 2020-2021
• UCI 2022-2024
• 2020 NCAA D1 Champion (UCLA)
• 2022 GCC New Comer of the Year
• 2022 GCC second team

2024 (Senior)

• Big West Player of the Week (Oct. 30)
• Third on the team with 61 points
• Scored 25 goals 
• Recorded 61 shots 
• Dished out a team-high 36 assists 
• Added 18 steals and eight field blocks 

2023 (Junior)

• Scored 23 goals
• Recorded 60 shots
• Dished out 24 assists
• Added 17 steals and nine field blocks

2022 (Sophomore)

• GCC Newcomer of the Year
• All-GCC Second Team
• ACWPC All-American Honorable Mention
• Scored 53 goals 
• Recorded a team-high 29 assists
• Had a team-high 22 steals

At UCLA

• ACWPC All-Academic Honoree (Excellent- 2020)
• MPSF All-Academic Team (2021)
• Pac-12 Fall All-Academic Team (2020)
• UCLA Athletic Director's Honor Roll (Winter 2021, Spring 2021)
• Played in 11 total games
• Recorded three goals, 14 shots, nine assists, and six steals

Career Highs

• Goals: 6, vs. Fordham (09/24/2022)
• Assists: 6, vs. UC San Diego (10/11/2024)
• Steals: 4, vs. California Baptist (09/30/2022)
• Field Blocks: 2, Four times (last vs. UCLA, 09/13/2024)
• Drawn Exclusions: 3, Twice (last vs. Long Beach State, 09/22/2023)

Harvard-Westlake School

• Two-time D1 CIF Southern Section Champions (2018, 2019)
• Two-time CIF Southern Section First Team All-American (2018, 2019)
• Los Angeles Daily News All-Area first-team honors (2019)
• 18U Super Finals MVP (2019)

Personal

• Brother played water polo
• Hobbies include snowboarding and metal welding

 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.  

Coach Sebastian Cordoba brings a legacy of passion, skill, and dedication as the head coach of Patriot Swim Club. Born in Colombia, Sebastian’s swimming journey began in the warm waters of his hometown, where his mother instilled in him a love for swimming. By age 14, he was already teaching swim lessons, uncovering his natural talent for coaching and a gift for inspiring others. Today, with over 20 years of experience, he embodies a blend of dedication, technical expertise, and infectious enthusiasm that ignites Patriot Swim Club’s competitive spirit. 

Sebastian’s early athletic career was marked by exceptional talent across multiple sports. At just 10, he earned a place on his state’s team in European handball, volleyball, and water polo, eventually focusing his passion on aquatics. His commitment took him to the Colombian National Team in water polo, where he represented his country internationally in Argentina, Brazil, and Mexico. This level of competition fueled his understanding of high-performance athletics, knowledge he now shares with Patriot Swim Club swimmers. 

After moving to the U.S. at 19, Sebastian continued his education and swim training at American River College in California, where he competed in the 2007 and 2008 State Championships. His journey continued at Vanguard University, where he earned a dual sports scholarship in water polo and swimming. As captain of Vanguard’s water polo team, he led his squad to Nationals, and in swimming, he excelled as part of a 200 freestyle relay team that placed in the top 10 nationally. Graduating with a degree in Business Administration and Marketing, Sebastian’s academic and athletic balance became the cornerstone of his coaching philosophy. 

Beyond his role as a seasoned coach, Sebastian is also a father with a vision. He founded and developed Patriot Swim Club to create a path for his daughter, Camila, and all young swimmers like her to compete at the highest levels of swimming. 

With over 20 years of experience, Sebastian’s journey—from representing the Colombian National Team in water polo to leading Vanguard University’s swim and water polo teams—has shaped a unique coaching philosophy. He’s committed to bringing every swimmer the same level of opportunity, growth, and guidance he strives to give his own daughter. With over a decade in coaching, Sebastian is a trusted leader within the Irvine swim community. Known for his meticulous approach to technique, his focus on building personal connections, and his unwavering support for each swimmer’s journey, Coach Sebastian emphasizes an environment where athletes feel encouraged to achieve greatness both in and out of the pool. His philosophy extends beyond the lanes, encouraging swimmers to excel academically and prioritize their holistic growth. 

Joining Patriot Swim Club means becoming part of a team driven by excellence, inclusivity, and passion. Coach Sebastian has designed a program that supports swimmers at every level—whether you’re diving in for the first time or training for elite competition. His leadership is built on values of teamwork, resilience, and joy in the sport, helping every Patriot swimmer thrive. 

So, if you’re ready to push your limits, join Coach Sebastian and the Patriot Swim Club family. Under his guidance, you’ll grow as an athlete, achieve your goals, and make memories that last a lifetime. The pool is ready—are you? Jump in and start your journey with Coach Sebastian today!