The Blades went two ahead with quickfire goals from Sander Berge and Billy Sharp in the first half, with Jack Robinson and the superb Morgan Gibbs-White on target in the second.
Boro got on the scoresheet through Folarin Balogun, after a rare slip from Wes Foderingham, but United were full value for a rousing victory against a serious promotion rival – managed by their old boss Chris Wilder, who was given a good reception on his return to his boyhood club ahead of kick-off.
But who was United’s man of the match? Click through our photo gallery to see our man’s ratings – including a VERY rare perfect 10 …
1. Wes Foderingham 5
Had a moment to forget for Boro's opening goal as he slipped when kicking and presented an easy chance to the former Blades target Balogun to score. Solid otherwise Photo: Simon Bellis
2. Ben Osborn 8
Handed a start at right wing-back to add to the collection of positions he has played for the Blades, Osborn's performance was one of typical tenacity and no shortage of quality either. A player well worth offering another contract. Picked up an assist too for Gibbs-White's stunner Photo: Andrew Yates
3. Ben Davies 8
Another player out of position on the right of defence, you wouldn't know if you didn't watch United regularly. Just looks a class act Photo: Andrew Yates
4. John Egan 8.5
Defensively sound all evening and picked up an assist with an intelligent header back across goal for Robinson to volley home. Photo: Andrew Yates