Teenager Paul Digby has signed a new contract that will keep him at the club until 2017.
The 18-year-old, who missed the whole of last season with injury, has impressed in pre-season and is thought to have been watched by other clubs.
Sheffield-born Digby, who has played four first team games, said: "Last week, I sat down with my agent and he said that the club wanted to keep me here for the next four years. We discussed various things and obviously I was thrilled.
"It's such a big deal for a young player. To know I'm wanted as part of the club's future plans gives me a massive boost."
