Stephen McManus has returned to Middlesbrough from his loan spell at Bristol City to help provide cover, with Tony Mowbray's men lacking numbers at the back.
The Teesiders lost their two first choice centre halves, Seb Hines and Matthew Bates, to injury in the 1-1 draw with Ipswich Town last week.
Robins boss, Derek McInnes, admitted that he was disappointed to lose the services of the 29 year old but said he understood Middlesbrough's reasons.
'We're obviously disappointed to lose Stephen, but we know this can happen as part of the loan system. We thank him for his time here, I know he enjoyed his brief spell.
'It's a shame because I feel he had so much more to offer, but we understand the need fromMiddlesbrough to recall him given their current injury crisis.
'It's one of the reasons we strengthened our defensive line before the deadline last Thursday. Now we have to go with what we've got for the rest of the campaign.'