West Ham United look for cover for the injured Aaron Cresswell.
The highly-rated Charlton Athletic left-back has been the subject of a bid from Birmingham City, who had been hoping to tie up a transfer, but a possible exchange deal with David Davis has held that up.
Now West Ham are ready to come in with an offer for the 22-year-old, who has come through the youth ranks at The Valley.
Fox has already been on West Ham's radar for a couple of years and they considered him before signing Cresswell himself. Now they believe he could be the ideal man to bolster their squad.
Cresswell was injured earlier this month in a pre-season game with Karlsuher and West Ham do not expect him to return to first-team duties until January at the earliest.
And while West Ham do have some players who could fill in, such as Sam Byram and Michail Antonio, Fox would offer them a like for like option and they have made contact with Charlton.
They also have Scottish youngster Stephen Hendrie on loan at Championship Blackburn Rovers, but they would rather he gained first-team football at Ewood Park than recall him too soon.