Diablo Alliance Coaching Staff

The Diablo Alliance coaching staff includes former Olympians, USA National Team Members, NCAA National Champions, College and High School All-Americans and current local Varsity High School Coaches. Each of our coaches work hard to focus their attention on the particular skills and disciplines that are appropriate for the level of athlete under their guidance. Our coaches take special interest in both building individual skills as well as team concepts to ensure our athletes progress together and participate at all levels. As water polo is a team sport we encourage group activities both in and out of the pool and coordinate team social activities with each age group team during each session and at tournament weekends.

Below is a listing of our wonderful group of coaches:

Robby Arroyo

12u/10u Head Coach & Club CEO

Robby became passionate about water polo at a young age. He has won major water polo events like National Junior Olympics, Champions Cup, CIF-SS D1, MPSF Conference, and many more including with Team USA and Professionally. While in high school he trained with the 1996 Olympic Team alongside his older brother Gavin. Robby has been focused on expanding the sport of water polo for both boys and girls at multiple levels along with hosting local tournament opportunities to aid in the expansion of the sport (CCCA Regional & State Championships, CAL Cup, ODP National Championships, etc.). Below are some of Robby’s water polo accomplishments:

  • Diablo Alliance Head Coach (2016-Present)
  • Acalanes HS, Boy's Head Coach (2018-Present)
  • Las Positas College, Head Men's Coach (2015-Present)
  • Lamorinda Water Polo, Head Coach, 14U Girls (2012-2016)
  • California State University, Long Beach - Volunteer Coach (2006-2008)
  • Golden West, Head Coach 18U Boys (2005)
  • Foothill High School - Assistant Coach, Men's Varsity (2005)
  • Pinole Valley - Head Coach 18U Boys

As a Player:

  • USA National Team
    • Member of the USA Youth, Junior and National Teams (1992 - 2000)
    • USA "Top16" Swimmer, US Swimming Jr. and Sr. Nationals
  • Played Professionally in Greece, Spain and Hungary
  • University of California, Berkeley:
    • 4 Year Starter
    • MPSF Champion and NCAA Runner Up (2002)
    • Team Captain and member of hiring committee for head coach (2002)
  • Runner-up at Men's Outdoor Nationals, NYAC (2002)
  • SOCAL, Won several NJO Championships & Inaugural Champions Cup (1987-1998)
  • Foothill High School, Santa Ana, CA (1994-1998):
    • 4 time All American, All CIF SS, All OC County, All League in Swimming and Water Polo
  • CIF SS Water Polo Player of the Year (1997)
  • Played in 3 CIF Championship Games--Winning in 1995

Catharine von Schwarz Arroyo

18u Head Coach and Club COO

Cat has been involved with water polo with water in some way or another since she was 12 years old. The sport has given her so much and she could not imagine what her life would be like without it. Born in Annapolis, Maryland there was not much opportunity for girls playing water polo, so she played with the boys. From there she was recruited to play at UCLA and went on to play with the US Team and was the first American woman to play professionally in Italy. Some of Cat’s water polo accomplishments are listed below:

As a Coach:

    • Diablo Alliance Head Coach (2016 - present)
    • USA National Cadet Team Assistant Coach (2016 - present)
    • Olympic Development Program (2010 - present)
      • 11th/12th grade Head Coach, Pacific Zone (2012 - 2017)
      • 11th/12th grade Head Coach, Pacific Northwest Zone (2010 - 2012)
    • Lamorinda Water Polo, Girls Program Director (2012 - 2016)
    • St. Mary's College, Moraga - Head Coach (2012 - 2016)
    • Campolindo High School, Assistant Coach (2012 - 2016)
    • California State University, Long Beach - Head Coach (2006 - 2008)
    • Los Angeles Water Polo Club (2004 - 2006)
    • University of California, Los Angeles - Assistant Coach (2003 - 2004)
    • Golden West College - Assistant Coach

As a Player:

    • Professionally:
      • Rari Nantes Florentina, Florence, Italy (2004 - 2005)
      • I.G.M Ortigia, Sircusa, Sicily, Italy (2001 - 2002)
    • US National Team:
      • Senior National Team (1995 - 2003)
      • Junior National Team (1990 - 1996)
    • Collegiate Career:
      • Member of UCLA Athletics Hall of Fame (2010)
      • 4 time NCAA Champion (1996, 1997, 1998, and 2000)
      • University of California at Los Angeles (1996 - 2000)
    • Club Career:
      • New York Athletic Club (2001 - 2013)
      • Naval Academy Aquatic Club (1998 - 2001)

Brook Rogers

18u Assistant Coach


Jessica Laurence

16u Head Coach


Jess started her water polo career in 2003 with Golden Bear water polo. She then moved to 680 Drivers water polo club in 2008 as a player and then transitioned to a coach in 2012. During her time at 680, she was the assistant for the 14u A team and head coach of the 12u A team. Her first year coaching the 12UA team they placed 6th at JOs. Jessica graduated from Monte Vista High School where she was a four-year varsity player and senior captain. Then Jessica attended Cal State Monterey Bay where she played 4 years of Div II water polo and was a senior captain as well. She then moved back to the Bay Area where she attended Saint Mary’s College and received dual credentials and Masters in Arts of Teaching. In 2016-2018, Jessica was the JV head coach and varsity assistant at San Ramon Valley High School. In 2017, Jess was awarded 2017 Top Coach Award: ODP Development Team. She is also currently the USA Development National Team Manager, Head PAC Zone Development Coach and National 11 and Under Program Director. In 2018, she became the Head girls’ varsity coach at Monte Vista High School. When she is not on deck you can find her in the classroom teaching English and AVID at Monte Vista High School.

Todd Halvorson

16u Head Coach

Todd has over 22 years of coaching experience and numerous accomplishments to his name. His teams continually finish in the top tier of every tournament and rank as one of the top age group teams in the Nation. In addition he has sent 3 players on to play in the Olympics.

He currently lives in San Ramon with his wife Hillary and has two children, Drew and Dylan. His daughter Drew currently plays water polo and UC Santa Barbara and his son plays at California HS.


  • 1997-Present: As a high school coach he has won 5 North Coast Section Championship Titles and 6 EBAL League Titles
  • 2000-13: ODP Head Coach, for 13 years, of the Pacific Zone 8th Grade and Under Girls Olympic Development Program.
  • 2003 – Awarded Coach of the Year by the Contra Costa Times Newspaper
  • 2006 – Awarded Volunteer Coach of the Year by USA Water Polo
  • 2013-15: Women’s Assistant Coach Team USA, Development National Team
  • 2013 – National Champions Junior Olympics Gold Medal 14U
  • 2013 - Bronze Medal 3rd Place in the Nation 12U Coach
  • 2013 – Awarded National Development Coach of the Year by USA Water Polo to the top age group coach in the nation.
  • 2016 – Silver Medal 2nd Place in the Nation 16U Assistant Coach
  • 2016 – Distinguished Coaching Award given out by USA Water Polo


Brad Guslani

16u Assistant Coach



Mischa Buchel

14u Head Coach


Misha has been a member of the Diablo coaching staff since 2005. He began his water polo life at Clayton Valley High School in Concord where he was a 1st Team All-NorCal player. After graduating from UCSD with a degree in Bioengineering, he began coaching the boys and girls teams at La Costa Canyon High School in Carlsbad, CA. Since moving to northern California in 2005 Misha has coached the varsity girls water polo team at Acalanes HS, leading them to the NCS championship game two of the last three years. When he’s not coaching water polo, he’s either teaching math at Acalanes HS (where he was named Teacher of the Year in 2012), or spending time in the outdoors with his wife Brittany and sons Jonas and Peter.

Scott Turner

14u Assistant Coach

Scott began his water polo coaching career helping with his oldest daughter back in 2011 in age group water polo. He enjoyed working with the children and wanted to give back to the sport that he had played since he was in 8th grade, that he volunteered to be the JV Coach at Monte Vista High School in 2012. The following year he took over the Varsity coaching position and coached for the next 4 years, ending in 2016.In 2017, he decided to leave the high school coaching ranks, because his youngest daughter Maile decided to play water and now he helps with the 14-U at Diablo Alliance.

His philosophy is hard work and good fundamentals can make any player improve.

Some of Scott’s water polo accomplishments are listed below:

  • High School in Hawaii
  • Attending UCLA from 1990 – 1995. Four Year Letterman.
  • Captain for the 1994 Season
  • NCAA 2nd Place (1991)
  • NCAA 4th Place (1994)
  • Second Team All-American (1994)
  • 1st Team MPSF (1994)
  • Played for the US National B Team (1994)
  • Varsity Coach – Monte Vista High School Water Polo (2012 - 2016)
  • Coach - Diablo Water Polo (2015 - present)


Jim Hassett

10u, 12u & 14u Assistant Coach

Jim brings over three decades of experience in swimming and water polo to Diablo Alliance. His accomplishments starting from his days at Washington High School in Fremont to swimming in the 1996 Olympic Trials and playing water polo in numerous FINA Masters World Championships are listed below:

Swimming:

    • NCS Champion 200 Free (1990)
    • High School All-American
    • 1991 NCAA D2 Champion in 200 & 500 Free, 400 & 800 Free Relay (Cal State Bakersfield)
    • 1992 NCAA D2 Champion in 200 & 500 Free, 200 Back, 400 & 800 Free Relay (CSUB)
    • 1994 NCAA D1 9th place 200 Free, All American (UC Berkeley)
    • 1995 NCAA D1 7th place 200 Free, All American (UC Berkeley)
    • 1996 participated in US Olympic Trials in 200 Free (Ft. Lauderdale Swim Team)

Water Polo:

    • 1989 & 1990 All League, Washington High School, Fremont, CA
    • 1996 & 1998 1st Team All Conference Ohlone College, Fremont, CA
    • 2004, 2010 & 2014 FINA Masters World Championships Bronze Medalist
    • 2006 & 2008 FINA Masters World Championships 4th place
    • 2010 & 2015 US Masters Gold Medalist

Coaching:

    • 1999 Head Coach Boys Varsity Swimming, Los Gatos High School
    • 2010 Head Coach Girls/Boys JV Swimming, Santa Cruz High School
    • 2013-15 Assistant Coach 10U Girls/Boys Wax-em Water Polo, Santa Cruz
    • 2015 Assistant Coach Boys Varsity Santa Cruz High School (SCCAL Champions)

Fran Usedom

Diablo South Head Coach & Co-Director

Fran has been enjoying coaching water polo for 12 years. Starting out as a swimmer, Fran got a taste of water polo back in the day while playing for Ohlone College’s inaugural women’s team. She went on to play club water polo at Chico state and then help start a club program at Cal State Hayward, where she received her BS in Kinesiology. In 2003, Fran and her husband, Randy, established the water polo teams at Foothill High School. She operated Stoneridge Water Polo from 2006-2009. Some of her favorite memories, over the years, were watching her 3 children (Rachel, Daniel & Jeremy) play water polo.

Coaching History

    • 2003 – Present - Foothill High School Varsity Girls
    • 2013 – 12, 14 & U, Spring and Summer Club Water Polo Castlewood CC
    • 2009 – 2012 –12 & Under Beginners, 680 Drivers
    • 2004-2009 – 12 & U coed; 16 & U Girls - Stoneridge Water Polo Club, Pleasanton


Andre Weiglein

Diablo South Head Coach & Co-Director

Andre began his coaching experience managing his boys’ little league baseball teams. Falling in love with coaching through the experiences with his sons and their friends hooked him into coaching and enticed further involvement in coaching the sport he’s been playing most of his life, water polo. His passion for teaching water polo is driven by the countless positive experiences he had with his excellent college, high school and club coaches and many close friends gained throughout his playing career. Andre’s water polo accomplishments are listed below:

    • High School All-American
    • Two Time NCAA Champion (1984, 1987)
    • NCAA 2nd Place (1986)
    • Co-Captain, 1987 UC Berkeley Men's Water Polo Team
    • Three time USWP Masters All-American
    • 7 USWP National Championships - Olympic Club
    • 10 Masters National Championships - Olympic Club
    • 3 Masters World Championships - Olympic Club
    • Member, Olympic Club Hall of Fame
    • Coach - Foothill High School Water Polo (2014 - present)
    • Coach - Diablo Water Polo (2015 - present)


Jane Bergez

Head Pee-Wee Coach

Jane has been coaching for Diablo Alliance since 2017. She began her water polo journey in the 7th grade where she played club polo for CORE Water Polo Club and Academy Water Polo. She continued her career in high school with the Carondelet Cougars and is currently studying at Diablo Valley College. What Jane loves most about water polo is how close you can become to your team in such a short period of time. She loves the fast pace of the game and freedom to be able to play within a system while still being creative.


Molly Barnes

Consulting Coach

  • Head Coach – Campolindo HS JV (2014 – Current)
  • Head Coach – Cal State Northridge University (2000 – 2007)
    • 2007 – Finished 11th in MPSF; ranked 15th in the country; 2 players selected All-MPSF; 1 player All-American CWPCA; 9 players Academic All-Americans CWPA
    • 2006 – Finished 12th in MPSF; Top 20 in the country; 2 All-Americans CWPCA
    • 2005 – Finished 8th in MPSF
    • 2004 – Nationally ranked 15th
    • 2001 – Named Inaugural Head Coach
  • Volunteer Assistant Coach – LOYOLA MARYMOUNT UNIVERSITY (2001)
    • 2001 – Finished top 3rd at NCAA
  • Assistant Coach – Loyola Marymount University (1998 – 2000)
    • 1999 – Qualified for Collegiate Nationals
    • 1998 – Named Inaugural Assistant Coach
  • Athlete – UCLA (1994 – 1997) & UC Berkeley (1992 – 1993)
    • 1997 – NCAA CHAMPION (Water Polo)
    • 1996 – NCAA CHAMPION (Water Polo)
    • 1994 – Member Inaugural Soccer Team and Team Captain
  • Athlete – Monta Vista HS (Cupertino, CA)
    • Five Sport Athlete (water polo, swimming, soccer, field hockey and basketball)
    • 4 X MVP of the Swim Team
    • All-American and CIF Champion in Swimming Relays
    • CIF Runner-Up in Field Hockey and Basketball
    • Defensive MVP and most inspirational player in Soccer
    • National Scholar-Athlete Recipient

Mary Collie

Consulting Coach

Mary came to water polo from the swimming side of things. As a college swimmer at Southern Connecticut State University she played polo during the off-season as a way to stay in shape with her team. She started coaching water polo at the Webb Schools in Claremont in 2002, and now coaches the girls team at Marin Academy where she is also an English teacher. In addition to coaching at the high school level, Mary coaches in USA Water Polo’s ODP program. She is the head coach of the pacific zone cadet team, and she was named USAWP ODP Coach Of The Year in 2016. She likes to focus on fundamental skills and a holistic understanding of movement in and out of the water. She is a certified Crossfit Level-1 trainer, a certified pilates instructor, a Roll Model Method trainer, a Level 1 mWod Mobility Coach, and an active athlete. She lives in San Rafael with her husband Jamie, son Q and Kerry, and two dogs.

Jamie Collie

Consulting Coach

Jamie started playing water polo at the McCallie school (an all-boys prep school in Chattanooga, TN) and was a part of the first high school team in Tennessee. He continued his playing career at the University of Richmond, and was a 4-year varsity player. His coaching career began in 2002 in Southern California at

the Webb Schools where he coached both the girls and boys teams. From there he moved on to Marin Academy where he currently coaches the girls team and teaches math. Along with coaching at the highschool level, Jamie is the Pacific Zone Chair for the USA Water Polo ODP program and the head coach at the youth level. He was named USAWP ODP Coach Of The Year in 2012. Jamie brings a holistic approach to his water polo coaching focusing on the whole athlete. His understanding of movement and mechanics help him support his athletes both in the

water and out. He is a Level 1 Crossfit Coach, a Level 1 mWod Mobility Coach, and an active athlete himself. He lives with his wife Mary, sons Q and Kerry, and two dogs in San Rafael.

Bennett Indart

Consulting Coach

Bennett brings over 30 years of water polo experience to Diablo and enjoys mentoring and coaching young athletes in water polo as a volunteer coach. Bennett’s coaching philosophy is based on building upon sound fundamentals, hard work and teaching balanced offensive and defensive principles. Some of Bennett’s water polo accomplishments are listed below:

    • Three Time High School All-American
    • Two Time NCAA Champion (1987, 1988)
    • NCAA Runner-up (1986, 1989)
    • 1989 NCAA All-American
    • USA Junior Team: Pan American Gold Medalist (1987) and Bronze Medalist(1985)
    • Co-captain, 1989 UC Berkeley Men's Water Polo team
    • Six time USWP Masters All-American
    • Co-founder and Chairman, Peter J. Cutino Award
    • Earned 4 Gold, 1 Silver and 3 Bronze Medals in FINA World Masters Championships
    • Member, Olympic Club Hall of Fame
    • Board Member, Friends of Cal Aquatics
    • Co-Head Coach - Monte Vista HS Women's Water Polo (2013 - present)

Mauren O'Toole Purcell

Club Founder and Consultant

Maureen "Mo" is widely regarded worldwide as the greatest female water polo player of all time. Maureen began her water polo career at Wilson High School in Long Beach, California, playing on a boys water polo team because there wasn't a girls team. At age 17 she joined the U.S. Women's National Team. From 1978 to 1994 she was a constant figure on the National Team; the only exception was in 1991 when she gave birth to the joy of her life, her daughter Kelly. Some of Maureen's many accomplishments are listed below.

  • Most Valuable Player of the US Women's National Team 15 times
  • U.S. Water Polo Female Athlete of the Year 5 times
  • World Water Polo Female Athlete of the Year 6 times
  • All American team for U.S. Water Polo a record 28 times
  • 2000 Olympic Games Silver Medalist
  • Inducted into the International Swimming Hall of Fame as an Honor Water Polo Player (YouTube Video)