The 17-year-old is the latest Academy graduate at St Andrew's to be handed pro terms having progressed through the ranks at the midlands outfit, signing a two-and-a-half-year deal.
Birmingham-born Gray has been with the club since the age of seven and made his first-team bow as a late substitute in a 4-0 Championship victory over Millwall in October.
He was then introduced as a first-half substitute at Derby before making his full Blues debut in last month's 1-0 home defeat to Charlton.
Gray has so far made a total of five appearances for Birmingham this term.
- Sports & Recreation