Brown, 20, will stay with the League One club for the remainder of the season.

Manager Gianfranco Zola has been impressed by Brown’s undoubted ability since taking charge but is keen that he gains more experience as competition for places at Blues has intensified.

Brown has made nine appearances for Blues this season, the last of which was at Newcastle United in the FA Cup Third Round replay. He has been a regular in the First Team matchday squad.

The England Under-20 international previously spent a loan spell at Notts County in 2014.

The Spireites are managed by Gary Caldwell, brother of Steven Caldwell, who will have seen Brown coming through the ranks when he played at Blues.