Began his career at the age of 16 in 2001 with Rugby United, but made only 1 appearance that year plus another as sub next season. It was in 2002-3 that he began to blossom, scoring his first goal against Stourport Swifts and going on to 30 appearances and 11 goals. He contributed more than 10 goals in each of the next two seasons before leaving with departing manager Tony Dobson in June 2005 to join Solihull Borough. Craig Dutton and David Pearson made the same move. Martin Hier was at Solihull at the time and Robbie Beard had just rejected a move in favour of Brackley.

Justin signed for AFC Telford in 2006. In his final season with Solihull, he was the club's leading scorer with 19 goals, despite breaking his leg midway through the campaign. Telford got his signature against fierce competition from Halesowen and Rugby Town. After continuing to suffer from injury problems, Justin was released on loan (we believe) to Bedworth United.

He signed for the Brakes only a matter of hours before making his debut against Chasetown on 8 March 2008 but signed for Brackley Town in May 2008 after making only a limited number of appearances for Leamington.