Aberdeen have already seen Angus MacDonald and youngster Lewis Carrol agree exits today.
Nottingham Forest are close to tying up a six-figure deal for 16-year-old defender Carrol, a highly-rated Scotland youth international.
While experienced centre-half Angus MacDonald was confirmed to have cut short his Pittodrie stay ahead of a possible move to Exeter City.
MacDonald had fallen further down the pecking order after the January signings of Mats Knoester, Kristers Tobers and Alfie Dorrington.
The Dons are hoping to conclude a deal for Palestinian striker Oday Dabbagh on loan from Charleroi.
But another exit now appears to be on the cards.
Leganes set to sign Duk from Aberdeen
Duk looks set to follow Carrol and MacDonald out of the Pittodrie exit door, according to reports.
Journalist Luca Bendoni claims Spanish side Leganes are close to signing the Aberdeen forward in a deal worth an initial £600,000 but with a significant sell-on clause.
The La Liga outfit had an offer for the Cape Verde international rejected on Saturday but have returned with an improved bid and agreed terms with Dons chiefs.
Duk went AWOL in the summer as he tried to force a move but returned and apologised to the club and fans before being welcomed back into the fold.
Dabbagh to Dons latest
Aberdeen hope to get Dabbagh over the line before the window closes at 11pm.
The 26-year-old was earlier completing a medical after a loan with an option to buy was agreed with Charleroi.
It came after the Dons missed out on AC Milan’s Marko Lazetić, currently on loan at Backa Topola in Serbia.