Chapman grew up in South Western Sydney and began playing organised football at the age of five with his local club Moorebank Sports.

[3][4] As a 14-year-old, Chapman received his first national team call-up to a Joeys training camp in Canberra and he subsequently played in two friendly matches against Japan.

Commitments with the Australian U20 national team, in preparation for the U20 World Cup, meant that he was unavailable for a number of Newcastle Jets matches during the 2012–13 A-League season.

[11][12][13][14][15] He was the youngest member of the inaugural A-League All Stars squad at just eighteen years of age and Coach Ange Postecoglou introduced him into the match in the 84th minute.

[16] This was Manchester United's only match in Australia during their 2013 pre-season tour of Australasia and a full array of first team players participated including Robin van Persie, Ryan Giggs, Rio Ferdinand and Danny Welbeck.

His injury saw him ruled out of the match day squad for several weeks, during which time he penned a one-year contract extension with the Newcastle Jets, despite strong interest from a number of other A-League clubs.

[20] The resulting travel commitments with the Australian U23 team meant that he was unavailable for a number of Newcastle Jets matches throughout January 2014.

Whilst in Oman, the Newcastle Jets parted company with Head Coach Gary van Egmond and appointed Clayton Zane as caretaker.

[21] In total, Chapman played nineteen matches for the Newcastle Jets A-League and NYL teams throughout the 2013–14 season with only one loss recorded during his appearances.

On 9 May 2014, the Newcastle Jets announced that they had mutually agreed to terminate Chapman’s contract amid reports he was about to be signed by Melbourne Heart.

Selection decisions aside, Melbourne City were not defeated in any of the matches that he played in during the 2016 FFA Cup competition and the 2016–17 A-League season.

[50][51] Connor was also selected into the U20 team that competed in Group E at the inaugural 2013 AFC U-22 Asian Cup qualification tournament in Indonesia and qualified for the finals.

[56][57][58] In June 2013, Chapman was selected into the Australian U20 team that were drawn in Group C at the 2013 edition of the FIFA U20 World Cup, alongside Colombia, El Salvador and the tournament hosts Turkey.

Despite finishing at the top of their group against Kuwait, Syria and Japan, Australia was eliminated at the quarter-final stage of the tournament in a 2–1 loss to Saudi Arabia.