United were defeated by an Anthony Martial hat-trick after going down 3-0 against Manchester United at Old Trafford.
On a sultry evening in Lancashire, the home side were on form as Martial completed a first career hat-trick with two in the first-half and one in the second to complete a three-goal success.
United manager Chris Wilder made five changes to his starting 11 following defeat at Newcastle. Simon Moore deputised for Dean Henderson who was unavailable under the terms of his loan from the Red Devils, whilst at the back Phil Jagielka replaced the suspended John Egan. In midfield John Lundstram came in for Sander Berge whilst in attack the fit-again David McGoldrick and Lys Mousset replaced Billy Sharp and Oli McBurnie.
The Blades provided the first telling cross of the game when Ollie Norwood threaded a terrific low pass into George Baldock in space down the right. In an advanced position, the wing-back sent in a dangerous cross forcing Victor Lindelof to make an important clearance.
Norwood was again involved soon after when he sailed a terrific long-range diagonal pass into the path of McGoldrick. The striker controlled, cut inside, before shooting from the angle but his effort was blocked.
Despite the positive opening, the Blades were hit with a sucker-punch against the run of play. Out of nothing Marcus Rashford burst towards the by-line before smashing a ball across the six-yard area where Martial stuck out a foot to divert beyond Moore.
The goal settled down the hosts as the Blades were forced to dig deep for a spell. It should have been 2-0 when Rashford combined with Martial who was running clear, but after Moore committed, the Frenchman turned the ball back to Rashford who somehow missed with the goal gaping, thanks to the close attentions of Jack Robinson.
On 18 minutes Moore was called into action as he parried a free-kick from Bruno Fernandes, whilst ex-Blade Harry Maguire saw a goal rightly chalked off after a push on Jagielka as he headed in a Fernandes corner.
The Blades regrouped after the drinks break and on 30 minutes enjoyed a sustained passage of possession inside the Manchester United half, which ended with a Lundstram strike which flashed over David De Gea's bar.
United grew in confidence and started to exert some pressure on the Manchester United goal. Twice Enda Stevens crossed from the left as the hosts were forced to make some crucial clearances.
After enjoying the best spell of the game, the Blades were dealt a blow just before half-time. Good work by Paul Pogba saw a pass to the right to Aaron Wan-Bissaka. He found half a yard on Stevens to work in a low cross and Martial was there again to convert to double the hosts' advantage.
Wilder made two changes at half-time with McBurnie and Berge replacing Mousset and Norwood.
McBurnie was almost straight into the action when patient play from the Blades ended with a Chris Basham cross which just eluded the head of the Scottish international.
The hosts enjoyed a good spell of possession, but the Blades held their shape as the Red Devils were unable to create anything clear cut.
It took until the hour mark for the next decent chance as Pogba showed great skill to dance his way through several challenges, but as he was about to shoot Martial took it away from him before blazing over.
On 64 minutes Wilder introduced Richairo Živković in place of McGoldrick.
Ten minutes later the game was sealed when Martial exchanged passes with Rashford before lifting the ball over the advancing Moore to complete his hat-trick.
Inside the final 10 minutes McBurnie tested De Gea from 25 yards but he didn't quite get the full contact he was looking for with the Red Devils 'keeper holding on diving to his right.
Man United: De Gea, Lindelof, Maguire, Pogba (Mata 79'), Martial (Ighalo 79'), Rashford (Perreira 79'), Fernandes (McTominay 79'), Shaw, Greenwood (James 79'), Wan-Bissaka, Matic.
Unused: Bailly, Fred, Romero, Williams.
Blades: Moore, Baldock, Stevens, Fleck, Basham, Lundstram, Jagielka, Norwood (Berge HT), McGoldrick (Zivkovic 64'), Robinson, Mousset (McBurnie HT).
Unused: L. Freeman, Sharp, K. Freeman, Verrips, Osborn, Rodwell.