Robbie Brady's agent has been told he hasn't "got it right" for the Republic of Ireland international by Neil Warnock.
The versatile player was released by Burnley at the end of last season, and has long been on a linked with a move to Celtic.
He had been touted with a move to Warnock's Middlesborough after a lacklustre start to the Championship season, reports The Daily Record.
However, the Riverside boss has played down the interest while taking a swipe at the 29-year-old's advisors.
He told TeesideLive when asked about any potential interest in Brady: “I didn’t see us linked with him, if I’m honest.
“Robbie Brady is a tremendous left-sided player with stacks of ability.
“I was surprised when he left Burnley. In fact, I think he was offered a new contract, so I’m not sure his agent has got it right for him.
“We are looking for that type of player on that side, out of contract.
“But you’ve got to be so careful because players like that won’t have been involved in any training with a squad and they’ll be behind. They’ll be training on their own.
“It’s all right looking, but unless the right one comes along, we’ll have to just muck on with what we’ve got.”
Ange Postecoglou has been left short on left-side defensive options this season following a shoulder injury to Greg Taylor.
It has left youngster Adam Montgomery as the only available left-back, with frozen out Boli Bolingoli unlikely to be given another chance by the Australian after a surprise start against Livingston.
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