[2] Thornton made his Twenty20 debut playing for the Sydney Sixers in the 2016–17 Big Bash League against the Brisbane Heat on 3 January 2017.
[5] Thornton was included in the Cricket Australia XI squad for the 2017–18 JLT One-Day Cup.
He took one wicket for the cost of 12 runs in three overs, generating some "eye-catching late movement" during the match.
[7] In December 2022, Thornton took 5/3 to help bowl the Sydney Thunder out for 15, the lowest score in a professional T20 match.
[8] On 1 November 2024, Thornton made his first-class debut for South Australia during the 2024–25 Sheffield Shield season.