Leicester defender Zak Whitbread has had his loan spell at Derby extended until the end of the season.
Whitbread, 29, joined the Rams in September on an initial three-month deal but a two-month absence with a calf injury has restricted the American to just three appearances. He only returned to the first-team squad on Boxing Day.
"Zak has been great when he has played," said Derby coach Paul Simpson. "He has been really unfortunate injury-wise, which has been disappointing for both him and us. But he is fit again now and he gives us great security at the back
"We have got Richard Keogh out injured at the moment and Michael Keane has slotted in, Jake Buxton has been a rock for us at the back as well, so extending Zak's loan gives us that left-sided centre-back option and we are delighted that he has agreed to stay with us."
Whitbread has made 21 appearances for Leicester since signing for the Foxes from Norwich in the summer of 2012.
Derby are currently second in the Sky Bet Championship table behind Leicester ahead of a tantalising meeting between the east midlands rivals at the King Power Stadium next week - a game which Whitbread will not be eligible to play in.