Nigel Clough has trimmed his squad further on Friday with two departures - one permanently and one temporary.
Marcus Williams has left the club after agreeing a settlement. The 27-year-old defender is now free to join Scunthorpe United on a permanent basis.
He played a total of 50 times for the Blades but has spent recent months on loan at Glanford Park.
Meanwhile, Sean McGinty has joined League Two outfit Northampton Town on a month's loan.
McGinty hasn't featured for the Blades since the Johnstone's Paint Trophy tie against Scunthorpe United in September 2013.
The 20-year-old, who signed the paperwork on Friday, could make his Cobblers debut against York City on Saturday.