Derek McInnes hopes Greg Tansey can recover his best form at St Mirren.
Tansey left Aberdeen last months after an injury-blighted 18 months at Pittodrie, which included an ill-fated loan spell at Ross County, to join St Mirren.
The former Caley Thistle midfielder has made six appearances for Oran Kearney’s side and will return to the Granite City with his new club this afternoon.
The Aberdeen boss said: “He had a groin/hernia problem and he didn’t flag it up because he had only just come in the door and he played through it. He was motivated to do well but the injury overtook what happened and then it was hard for him to get in the team and get that regular football he wanted. It is disappointing but it wasn’t through a want of trying. He was a good boy and lad.
“He has good experience and I am sure his cause and focus will be on St Mirren and I hope he does well apart from today. I hope him signing there works out and it is not to say Greg can’t go on and really enjoy his time at St Mirren.”
Buddies manager Oran Kearney overhauled his squad in January in a bid to get them off the foot of the Premiership, with St Mirren three points adrift of Dundee at the bottom.
McInnes added: “It is maybe a bit more unpredictable because we are just out of the transfer window and we don’t know who will play but from their point of view they have made the changes they feel will help them stay in the league. They are in a three team fight to do exactly that. The season comes down to 13 games in the league. It is competitive at that end and the top end. We expect a tough game because their cause, in their eyes, is as big as our cause to win the game.”
Shay Logan is unlikely to feature with an ankle injury, while Scott McKenna is suspended. Goalkeeper Danny Rogers, who is on loan at St Mirren, is back at Pittodrie to rehabilitate a knee injury, which could keep him out for up to 10 weeks.