Colback spent the back end of last campaign on loan at Forest, and he did enough to impress Aitor Karanka.
Forest and Newcastle have been unable to agree a permanent deal for the midfielder throughout the summer so far, but there is still hope on the Reds’ behalf that a transfer could be done.
Colback appears to have no first-team future at Newcastle, with Rafael Benitez looking at other options, so they are unlikely to stand in the former Sunderland man’s way, if Forest do make a bid.
Colback is no longer said to be Forest’s only midfield target though, with Karanka making contingency plans, in case a transfer proves to be too complicated.
Forest are reportedly still looking to add another four players this summer, despite being busy over the transfer window so far.
Karanka has been handed a significant budget at the City Ground, with Forest expected to be a threat next term.