Dons boss Derek McInnes today admitted Scott McKenna could be sold in January.
Aberdeen rejected a £7 million bid from Championship Aston Villa on transfer deadline day for the defender.
However, McInnes confirmed the Scotland international could move on as early as the new year if a high enough bid comes in with enough time to replace him.
McInnes confirmed Villa pitched in with a late bid for the 21-year-old, who is contracted until 2023.
It was knocked back because it did not match the Dons’ valuation and there was not enough time to find a replacement.
That could change as early as the next transfer window.
McInnes said: “We will develop Scott here over the next few months.
“And if the January window comes in and there is an offer that gives us a wee bit more assurances on the figure and certainly more time to react to it – whether it is January, next summer or beyond – McKenna will move from here and go on to represent Aberdeen and Scotland in the future very, very well.”
Aberdeen also rejected a £3.5m bid from Celtic for McKenna during the window.
McKenna was ruled out of the 2-0 loss to Kilmarnock with a hamstring tear but is set to return for the game against St Johnstone after the international break.
McInnes insists it was vital the Reds retained McKenna as they face on-going defensive setbacks.
Centre-back Mikey Devlin is set to be suspended following his red card against Kilmarnock.
On-loan Watford defender Tommie Hoban is to undergo shoulder surgery and could be out for up to three months.
Centre-back Mark Reynolds is out for five months having undergone knee surgery.
McInnes said: “It was crucial we kept him.
“I had a conversation with Steve Bruce (Aston Villa manager) last Thursday and Friday (August 23 and 24) and he intimated they liked McKenna and may make a bid.
“We said if you do make a bid it needs to be within the next 48 hours or so.
“If you decide to make a bid the later in the window it is made there will be more resistance towards it. That is how it played out.
“Steve is one of the game’s good guys but when I saw his phone ringing me when we finished training on Friday morning it was never really going to be anything that would be welcomed by us at that late stage.
“How can you replace McKenna with five or six hours to go in a transfer window?
“The figure that they offered wasn’t enough anyway but certainly the timing was the biggest factor in all of it.
“We picked up an injury to Tommie Hoban and with Mark Reynolds out it is in not an area where we would have a lot of options.
“So we wanted to have enough time to try to address that if the offer had been significant enough for us to accept it.
“And it wasn’t.”
McInnes was frustrated at the decision to dismiss Devlin just five minutes into the game and refused to rule out an appeal.
He was also disappointed that referee Craig Thomson awarded a free-kick that Kilmarnock netted the opener from.
He said: “We will look at maybe appealing that if it is going to be worthwhile.
“But sometimes these things aren’t worthwhile.
“I feel disappointed with some of the decisions.
“It is tough when you go down to 10 men so early on.
“Rightly or wrongly, whether he has deemed that as the last man going through, that is debatable to say the least.
“We feel really aggrieved by the build-up to their first goal.
“It was actually the player’s bad control on his own arm and the momentum pushed it forward in his own path and he got that side of my full-back Max Lowe.
“That should have been deemed a hand ball.
“My first thought was Graeme Shinnie had won the ball when Craig Thomson blew for the free-kick.
“Brophy scored a fantastic goal over the wall which is well executed but there is a clear handball in the build-up.”