Gboly Ariyibi has signed a new two-and-a-half-year contract at Chesterfield.
The 20-year-old winger has impressed in recent weeks after being given his chance in the first team.
Spireites boss Paul Cook said: “Gboly is a very, very exciting young prospect who has great ability and pace.
“He is still developing as a player so there has to be some patience shown by fans as he learns the game.”
Ariyibi, born in Virginia, USA, was brought up in England and has represented USA U20s.
He made his debut in the JPT tie at Scunthorpe in September and has now made a total of eight appearances.