Forward Devante Jacobs is continuing to work on his fitness ahead of the new season under the supervision of the club's medical staff.
The 18-year-old made his debut for the first team last season against Preston North End coming on as a second half substitution.
Manager Darren Kelly said: "We have given Devante a specific programme to get himself fit for the new season.
"If Devante follows that programme and comes back in good condition and looks sharp, I truly believe he will become a great asset for the club."
Jacobs added: "I'm really thankful to the gaffer for the opportunity he has given me.
"I'm really determined to work hard, get fit and hopefully force my way into the manager's plans next season."