"If he doesn't go he will be competing to be in the team and I wouldn't put it past Stephen to see him at the heart of our defence for the rest of the season," said Mowbray, who this month gave a debut to summer recruit Josh Thompson.
"I will put on record what a fantastic man he is and what a fantastic player he has been for this club and if this deal doesn't happen he will be back on the training ground and striving to get himself in the team.
"He is a great leader of men and they are in shortage.
"I have just brought in two young centre-halves recently, I have brought in Jos Hooiveld, who is left-footed, and I have Darren O'Dea back from Reading."
Strachan was keen to be reunited with the player he made Celtic skipper in 2007.
"It has been well documented that Stephen is a big favourite of mine and he can't get a game at Celtic," Strachan told BBC Tees.
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