Stephen Warnock had been one of Leeds United's stand-out performers so far this season.
Derby County (@dcfcofficial) January 15, 2015
Stephen Warnock has been pictured holding up a Derby County shirt following the completion of his transfer from Leeds United earlier today.
The defender moved to the iPro Stadium for an undisclosed fee, signing an 18-month deal with the Rams.
The move serves as a major blow for Leeds, who are fighting against the drop in the Championship this season.
Warnock, who has been injured since Leeds defeated Derby last month, had been one of their most impressive performers to date and the loss of his quality and experience is likely to harm Neil Redfearn's side in the second half of the season.
The left-back has left a relegation battle for a title fight and he is is set to become a key figure in Steve McLaren's side as they gun for promotion.
Derby are currently in second place in the Championship and are looking one of the strongest outfits in the Football League.