Here's a catch-up on all the players who the Blades bought and sold a decade ago...
13. Bought: Mikhel Aksalu from FC Flora
The thinking man's Mart Poom, Aksalu never actually played a game for the Blades due to injury problems. He's now at Finish side Veikkausliiga, and still plays for Estonia. (Photo by Jan Kruger/Getty Images) Photo: Jan Kruger
14. Sold: Sun Jihai to CD Tiangcheng
The former Manchester City ace went on to rack up 80 caps for China, and finished his career at Beijing Renhe, before hanging up his boots in 2016. (Photo: Ian Kington/AFP/Getty Images) Photo: IAN KINGTON
15. Sold: David Carney to FC Twente
The ex-Australia international put in some fine displays for the Blades, before being snapped up by FC Twente. Now 35, he was last on the books at Sydney FC. (Photo by Jack Thomas/Getty Images) Photo: Jack Thomas