Derek Clappis joined the Pacific Men's and Women's Water Polo programs as an assistant coach in the 2021-22 season and was promoted to associate head coach for the men's team in advance of the 2025-26 year. Clappis is responsible for domestic recruiting and player development for both teams.
As part of the coaching staff, Clappis assisted the Tigers to an 18-2 overall record including a perfect 6-0 mark in the West Coast Conference in 2024. It resulted in a WCC Regular Season Championship.
In 2022, Clappis was part of a Pacific men’s team that won the Golden Coast Conference Championship and advanced to the semifinals of the NCAA Tournament after beating Cal in the quarterfinals 11-7. The Tigers finished 22-7 overall.
In addition to his duties with the Tigers, Clappis was been a part of USA's U20 National Team in various capacities. He was a part of the nation's 2025 silver medal at the World Aquatics Championships in Zagreb, Croatia which saw USA knock off Serbia in the quarterfinals and Hungary in the finals.
Prior to Pacific, Clappis coached Big Valley Water Polo Academy for seven years. He also traveled to Canberra, Australia after college to coach and play water polo at Canberra Water Polo Academy and Nordek Water Polo Club.
Born and raised in Stockton, Clappis played for the Tigers from 2013-17. He was part of a National Championship Runner-Up team in 2013, National Championship Semifinalist team in 2017 and GCC Conference Tournament Championship Team in 2017.
Clappis earned his degree from Pacific in business administration with a concentration in finance.
