Jack Carleton Duncan (born 19 April 1993) is an Australian goalkeeper who plays for A-League Men club Melbourne Victory.
In 2010 Duncan signed for A-League club Newcastle Jets from NSW Premier League side Sutherland Sharks. He made his professional debut in the 2011-12 A-League season on 19 November 2011, in a round 7 clash against Brisbane Roar.
On 2 May 2013, Duncan joined Perth Glory.
On 15 May 2015, Duncan signed a 2-year deal with Randers FC. He made his Danish Superliga debut on 16 May 2016 for the club in a 3âÂÂ2 away victory over Viborg FF. In June 2016, Duncan asked to be released from his second contracted year with Randers FC because there was no indication to him becoming first choice.
On 24 June 2016, Duncan returned to Newcastle Jets, signing a 2-year deal.
On 31 July 2018, Duncan joined Saudi club Al Qadsiah, after triggering his release clause.
On 21 December 2020, Duncan returned to Newcastle Jets for a third spell, after two years in Saudi Arabia.
On 9 June 2023, Duncan joined New Zealand A-League Men club Wellington Phoenix, to provide competition for Alex Paulsen after the departure of Oli Sail to Perth Glory.
On 8 July 2024, Duncan Joined Melbourne Victory on a 1 year contract.