Sinclair played at Newport Harbor under Coach Jason Lynch and became an All-American at UC Santa Barbara for Olympian Wolf Wigo.
He has coached the Corona del Mar girls the past two seasons after taking over for Sam Bailey, who departed for Beckman. The Sea Queens reached the CIF-SS Division 1 semifinals this past season, falling to eventual undefeated champion Laguna Beach.
Updated: Sinclair resigned Monday as Corona del Mar's girls coach as well as the girls club director for CdM Aquatics.
Sinclair's hiring concludes a long coaching search for Newport Harbor and pairs him with Olympic gold medalist Aaron Peirsol, who is the Sailors' boys swim coach.
Sinclair and Peirsol were classmates at Newport Harbor. Peirsol graduated in 2002, one year ahead of Sinclair.