Saints are demanding the 27-year-old's £18k-a-week wages in full.
"That is steep for Championship budgets where the maximum salary is probably around £10,000 a week," Mandaric told the Sheffield Telegraph .
"You can't criticise the club because that is their prerogative.
"But what I don't understand is the player just sitting there and not playing. Why not a sensible situation? Why not put him on the stage to move on?"
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