Almost the entire left side of Paul Heckingbottom’s defence has been decimated by injury already this season, with other fitness issues also hitting key areas at various times so early in the campaign.
The Blades have only two fit, senior wing-backs, one for either flank, and no natural left-centre halves. The left of their midfield has been hit by the absences of John Fleck and Ben Osborn, while skipper Billy Sharp hasn’t played since the draw at Middlesbrough earlier in the season.
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United have given themselves the option of registering one free agent before January after submitting only 24 senior players to the EFL, leaving Jack O’Connell’s name off their 25-man senior squad list.
And if injuries continue to bite at the back, they may be forced to draft in some cover. So here are 10 potential defensive options who left fellow Championship clubs over the summer … would you be happy if any of them came in at Bramall Lane, Blades fans?
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1. Lee Wallace
The ex-Rangers and Hearts player was released by QPR at the end of the season after spending three years at Loftus Road. Now 35, he operates at left-back Photo: Jacques Feeney
2. Sol Bamba
The popular former Middlesbrough defender had 'a few options' available after leaving the Riverside Stadium and is currently training with Bristol City, although that's thought to be more to keep fit Photo: Alex Livesey
3. Danny Rose
Formerly of Tottenham Hotspur, and Sunderland and Newcastle amongst others on loan, Rose had his contract terminated by Watford recently to leave him without a club Photo: Richard Heathcote
4. Danny Simpson
A Premier League winner with Leicester City, the 35-year-old has been without a club since his Bristol City contract was cancelled by mutual consent in March Photo: Alex Burstow