Sean Goss was signed from Exeter City for an undisclosed fee in the summer of 2012.
The midfielder, a boyhood United fan, impressed sufficiently as a guest player during the Ageon Future Cup in Amsterdam to earn a contract - despite being unfortunate enough to miss the penalty in the shoot-out defeat to hosts Ajax in the final.
A neat and skilful performer, he will look to press for a place in a congested area within Paul McGuinness' squad after scoring 13 times for Exeter's Centre of Excellence side in his final season.
Goss had been with the Grecians since he was eight years old but is adapting to life in Manchester and will aim to make his mark in 2013/2014 for the Under-18 team. Indeed, the early signs were very positive as he drew similarities to Michael Carrick with his playing style.
By both scoring and assisting goals, his performances were consistently of a high level as he nailed down a regular place in the engine room. Clearly becoming a key member of the side, he broke into the UEFA Youth League plans of Nicky Butt as well, albeit appearing at full-back for the Under-19s.