Love-him-or-loathe-him captain Richard Foster is set to finalise a £250,000 move to Bristol City today, according to several sources.
The pacey utility player was on a full-season loan to Rangers last term, and eyebrows were raised when Craig Brown made him club captain on his return.
However Brown will now have to seek a replacement for the armband, with influential midfielder Kari Arnason the fans' favourite for the role - if the Dons can hold on to him in the window.
The defensive hole left by Foster is set to be filled by former Motherwell captain Mark Reynolds.
The Sheffield Wednesday full-back, 24, has been frozen out at Hillsborough, making just six appearances this term.
Reynolds, who can play either at centre or left back, is now set to return to Scotland on a six-month loan deal with the Dons, and could go straight into the Dons squad for the Scottish Cup match with Forfar tomorrow.