Jack or Jackie Sinclair may refer to:
Jack Sinclair (baseball) (born 1999), American baseball player Jack Sinclair (footballer) (born 1995), Australian rules footballer for St Kilda Jack Sinclair (physiologist) (1927–2018), New Zealand neurophysiologist and middle-distance athlete Jack Sinclair (poker player) (born 1990), English professional poker player Jack Sinclair (rugby league) (1935–2006), Australian rugby league player Jack Sinclair (Scouting) (fl. 2004), president and international commissioner of Scouts Canada Jackie Sinclair (1943–2010), Scottish footballer
See also John Sinclair (disambiguation) Jonathan Sinclair (disambiguation)