Rafa Benitez has blunt message for Jack Colback at Newcastle
Colback – who was made available for transfer in the summer – has been training with the club's development squad since August.
Benitez will be without injured midfielder Mikel Merino for "at least" two weeks.
However, 28-year-old Colback will NOT be recalled to Benitez's squad as cover.
Asked about Colback's situation, United manager Benitez said: "He's training with the Under-23s. He knows the situation.
"We're working with the players available now. He knew our idea from the beginning.
"We have four or five midfielders. We didn't want to have six. I don't want too many players in the same position."
Ninth-placed Newcastle take on Bournemouth at St James's Park tomorrow.