Newcastle Jets On 18 December 2010, Pepper made his senior debut in a 4–0 loss to
Wellington Phoenix. On 14 February 2012 it was announced he had signed a two-year contract extension with
Newcastle Jets. Pepper has since cemented his spot in the starting XI with a string of impressive performances towards the backend of the 2011–12 season. This included a brace of goals in a 3–1 win away against a star-studded
Melbourne Victory side, and a deserved call-up to the youth international scene.
Western Sydney Wanderers On 9 June 2015, he was signed by the
Western Sydney Wanderers on a 1-year contract. On 29 June 2016, Pepper was released by the Wanderers.
Brisbane Roar In July 2016, Pepper joined
Brisbane Roar. Pepper made his Brisbane Roar debut in Roar's Round 1 clash against
Melbourne Victory, coming on for
Thomas Broich in the 74th minute. The game ended 1–1, after a 96th minute Brisbane equaliser. He spent most of the 2017–18 season as a makeshift central defender due to several injuries at the club, Pepper has started a total of 10 games at centre back so far this season, earning many plaudits for his performances. He left Brisbane Roar in March 2020.
Madura United After leaving Brisbane Roar, Pepper joined Indonesian club
Madura United. ==International career==