Chesterfield have signed Aston Villa midfielder Daniel Johnson on a three-month loan deal and Romuald Boco on non-contract terms.
Johnson, 21, is yet to make his competitive debut for Villa but spent time on loan in League One with Yeovil in 2012-13.
Boco, 29, spent last season with Plymouth, making 27 league appearances.
Both players could make their debut for the Spireites in Saturday's trip to Leyton Orient.
This is the fifth time Chesterfield boss Paul Cook has signed Benin international Boco, having signed him three times for Irish side Sligo Rovers and once for Accrington Stanley.
The duo also played together at Stanley in 2005-06.