Chesterfield have signed striker Jordan Slew on a deal until the end of the season and Cardiff defender Declan John on a one-month loan deal.
Slew, 23, was a free agent after leaving League Two Cambridge earlier this month.
John, 20, has been capped twice by Wales but has only featured once for the Bluebirds this season.
The pair could make their debut for the Spireites against fellow League One strugglers Crewe on Saturday.
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