Over the remainder of the 2003–04 season, Martin made seven more appearances for United's various youth teams, and was even named as an unused substitute for the Reserves in January 2004. The following season, Martin began as a regular in the Under-18s, but he was soon promoted to the Reserve team, where he began to flourish, scoring goals as well as setting them up, including a hat-trick in one game against Bolton Wanderers Reserves. The 2005–06 season was even more auspicious for Martin; after being named on the bench for two UEFA Champions League group games, he finally made his first team debut in the League Cup against Barnet on 26 October 2005. He was substituted after 75 minutes, allowing Darron Gibson to make his own first team debut, but he was a constant threat to the Barnet goal.