After seven years away from professional boxing Thornberry returned to the ring in 1993, initially suffering a defeat to Cruiserweight Colin Wilson but avenged it a few fights later.
In October 1996, Thornberry fought outside of Australia for the first time, challenging Henry Wharton for the Commonwealth (British Empire) Super Middleweight Title and suffered a fifth round defeat.
[1] Almost three years and just two victories later Thornberry got the surprise chance to travel to Germany and face undefeated IBF champion Sven Ottke.
Thornberrys final fight came at the end of 2002, the 34 year old suffering a late stoppage loss to future WBA World Champion Anthony Mundine.
During a search for erratic driving in Brisbane, police uncovered several bags of methylamphetamine and a loaded semi-automatic pistol.