Alan Wright was a target for the Blades boss this summer when his contract at Aston Villa ran out, but with a possible move to either Middlesbrough or Glasgow Rangers it came quite clear that United would lose out on the left-back.
Since then the former Blackburn Rovers and Blackpool defender has become out-of-favour in Paul McLaren's Red Army and a move to Bramall Lane might just re-start his career.
Neil Warnock told the club's official website (www.sufc.co.uk) "With such a small squad it is important to sign Alan with so many games coming up."
"I chased him in the summer but with Rangers and Middlesbrough also in the hunt I had to be patient."