Rotherham are unlikely to make any more signings before the end of the month, according to manager Steve Evans.
Derby captain Richard Keogh has agreed a new three-year contract with the Sky Bet Championship outfit.
James McFadden has completed his return to first club Motherwell.
The 29-year-old has signed a contract until the end of the season.
The Scotland forward, who scored 32 goals for the club as a teenager before a £1.25million move to Everton, had been training with the Clydesdale Bank Premier League club after leaving Sunderland last month.
The reaction to the hotly-anticipated news saw the Motherwell website crash immediately after the club announced the signing.
Manager Stuart McCall had earlier tried to dampen expectations over the return of the fans' hero, insisting he had not held discussions with the player but would do so after Wednesday's Clydesdale Bank Premier League clash with Dundee United at Fir Park.
However, the club were privately confident of signing McFadden following talks last week and they sealed the deal after their pre-match media conference.
McFadden could now make his competitive return in a claret and amber jersey on Wednesday night.