Castro joins the Gaels in 2026 after spending three seasons as the assistant coach at Harvard for their women’s water polo program. In 2025, the Crimson had a successful season going 10-2 in conference and 26-7 overall, winning their first ever CWPA Championship and making the NCAA tournament.

Prior to joining Harvard athletics, Castro spent time as the assistant coach for the women’s water polo program at Siena University. Towards the beginning of his career, he spent five years as the head coach for girl’s water polo at Torrey Pines High School, which made it to the 2019 CIF-SDS Division I Championship Game. Castro started off coaching at The Bishop's School with the boy’s water polo team, who won two open division CIF-SDS titles during his time there. He also spent time as the head coach for San Diego Shores Water Polo Club’s under-18 and under-16 teams.

As a player, Castro started off his collegiate career at San Joaquin Delta College, where he was named a First Team All-American and a First Team All-Big 8 Conference. Following his time there, Castro joined UC San Diego’s team and scored 11 goals and 8 assists. There, he earned his bachelor’s degree in human development and then went on to National University where he received his master’s in performance psychology.

Name	Title	Phone	Email Address
Stephen Loomis	Head Coach	(925) 212-0374	sl100@stmarys-ca.edu
Jacob Castro	Assistant Coach	(209) 662-0862	jc152@stmarys-ca.edu

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