Sinclair, who was 38, hadn’t been seen for a few days, but police have denied his death as being suspicious, and so a post-mortem will be carried out in order to determine the cause of death.
Players who had the chance to play alongside him described him as a “gifted player” who had “untapped ability” in a career that spanned over 3 teams totalling 80 games.
Sinclair was found after a concerned family member contacted police, as an investigation is underway into his death.
Former Balmain and Australian prop Steve Roach, is shocked to hear of Sinclair’s passing, whom he played two seasons with at Balmain.
“I used to marvel at his untapped ability,” Roach said. “He could play, don’t worry about that.”
Sinclair began his career with the Tigers in 1991, and played with them until 1993, before spending two seasons with the Bunnies. After that, he played for the Roosters in 1997, before he moved back to his first club, the Balmain Tigers for another two seasons.
“I know when I played against Jacin it was always a tough game,” former Australian captain Laurie Daley said.
“He was ultra-competitive and a gifted player. It is very sad news.”
NRL Chief Executive David Gallop was also saddened by the news, describing it as an “absolute tragedy”.