Arguably, the Blades could do with another central midfielder to boost their numbers, and here's six of them who could give United more depth in the middle of the park...
1. Remi Walter - Free agent
There's a number of sides chasing the former Nice midfielder, who is now a free agent. His relentless relentless style of play and positional versatility would be right up Chris Wilder's street.
Photo: VALERY HACHE
2. Matt Grimes - Swansea City
The slick-passing Swan impressed is fresh off the back of his breakthrough season, and has all the attributes to flourish in the top tier.
Photo: Stephen Pond
3. Mauricio Pereyra - Free agent
Known for his long-range strikes, the 29-year-old is currently a free agent after leaving Russian side Krasnodar following last season. He's got some useful Europa League experience in the bag, too.
4. Aaron Mooy - Huddersfield Town
The Terriers are said to want around £14m for the Australian ace, but Chris Wilder is known for his ability to drive a hard bargain, and Mooy's capture would be a real coup.
Photo: George Wood