Youth and collegiate

Sinclair was born in Laguna Beach, California and played water polo at Newport Harbor High School. At Newport Harbor, he won the CIF Championship in 2000 and was twice named Sea View League Most Valuable Player in 2002 and 2003. He was also named Second Team All-CIF Southern Section in 2002 and 2003.^[2] Following graduation, he enrolled at the University of California, Santa Barbara.

While in Santa Barbara, he played for the UCSB men's water polo team from 2003 to 2007.^[3] He was named a Third Team All American his final two seasons in 2006^[4] and 2007,^[5] which made him the 45th UCSB men's water polo player to earn All American status and the first under Wolf Wigo.^[6]

Club

His play impressed various pro teams and once he completed college he turned pro.^[7] He signed with Hunter Hurricanes of the Australian National Water Polo League and played in his first match on January 24, 2008.^[8] He ended the season with 63 goals, good for second highest in the league.^[9]

In the off-season, Sinclair joined Enfants de Neptune de Tourcoing based in Tourcoing, France.^[10] The stay was short-lived however as a string of poor results and an uncertain future led to Sinclair leaving the club.^[11][12]

Sinclair rejoined the Australian NWPL and signed with Victorian Tigers. His output dropped to 29 goals for the 2009 season.^[13]

Sinclair skipped the 2010 NWPL season, but rejoined Hunter Hurricanes for 2011,^[14] where he scored 46 goals.^[15]

For the 2012 season, Sinclair turned out for Drummoyne Devils,^[16] where he appeared in 17 games and scored 20 goals.^[17] He rejoined Hunter Hurricanes for his third tour of duty in 2013, where he netted a further 23 goals.^[18]