Jack Sinclair (born 12 February 1995) is an Australian rules footballer who plays for the St Kilda Football Club in the Australian Football League (AFL). Sinclair played TAC Cup with Oakleigh Chargers and played for Port Melbourne in the Victorian Football League (VFL).
Sinclair attended Scotch College with St Kilda teammate Jack Billings. He was drafted by St Kilda with the first pick in the 2015 Rookie Draft.
Sinclair made his AFL debut in Round 1 of the 2015 AFL season against Greater Western Sydney.