A Dubliner who has represented Republic of Ireland at all youth levels.
The hard-running centre-forward joined United in July after cutting his teeth with local side St Josephs, making his Academy bow at Southampton, and went on to rack up 26 appearances in all (19 starts) in his debut year.
Byrne scored four times and showed a real unselfish streak with his hold-up play and charging down defenders to create chances for others. He particularly impressed at the Aegon Future Cup in Amsterdam when United lost to Ajax in the finals on penalties.
More goals followed in 2012/2013 as he notched seven in 14 (5) games and hit a real purple patch in the second half of the term, most notably with a stunning display against Southampton at Carrington.
"Sam Byrne improved after Christmas when he started to look more powerful and positive and scored some good goals," commented coach Paul McGuinness. "That’s what a centre-forward needs to be doing."