Image source, Getty Images

Former Manchester United midfielder Paul Scholes is in scathing mood, telling BT Sport he "would be sat with my head between my hands after that performance."

He adds: "I've tried so hard to defend this team, but each week it gets harder. Every time I come to Old Trafford it's negative football.

"I would be depressed if I had been a part of that performance from Manchester United.

"The players are bored, fans are bored, everyone's bored. You look across at the bench and Van Gaal looks bored as well."

So was it a penalty? You be the judge. Click play and watch the incident within this live text.

Robbie Savage
Former Leicester midfielder on BBC Radio 5 live 606

"When Man Utd were in the Champions League and still challenging for the title then I thought you can't get rid of Louis van Gaal.

"But they're not going to win the league now, they're out of the Champions League.

"Look at Zinedine Zidane, a club legend, taking over at Real Madrid. So why not give the job to Ryan Giggs?"

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There's no doubt Manchester United dominated, but was it enough for you? Just two shots on target against a side 47 places below them is pretty damning.

Robbie Savage
Former Leicester midfielder on Radio 5 live 606

"When Louis van Gaal walked down the touchline there is usually applause but I saw a lot of fans with their thumbs down. Is this what Manchester United fans really want?"

Listen to 606 on BBC Radio 5 live now by clicking 'live coverage' at the top of this page.

Ed Sharples: Says a lot that I'm almost disappointed Manchester United have scored as it buys Louis van Gaal more time! #BBCFACup.

Eteyen Adegoke: That goal simply papers over the cracks. The play needs to change, Louis van Gaal needs to evolve, philosophy not working.

James Liggins: Talk about get out of jail for Man Utd… this lot just got out of Alcatraz with that penalty. #FACup #bbcfacup.

Robbie Savage
Former Leicester midfielder on BBC Radio 5 live 606

Image source, Reuters

"I thought it was a penalty but it was an absolute shocking performance from Manchester United. For me, Van Gaal, I'd get rid of him."

Listen to 606 on BBC Radio 5 live now by clicking 'live coverage' at the top of this page.

Chris Waddle
BBC Radio 5 live at Old Trafford

Image source, Reuters

"Man Utd struggled all game but in fairness to Sheffield United they came with a game plan and it nearly worked.

"The hosts just had to bring on Memphis Depay - he ran and committed defenders even if it was a soft penalty.

"It wasn't good from Man Utd but they're in the hat on Monday."

Louis van Gaal is on the pitch. A tap on the back of the head for Wayne Rooney but a scowling face on the Dutch manager. He must know some difficult questions are coming his way.

Hats off to the home side, they persevered and pushed until the death to get their reward. Take nothing away from them in that regard.

Sheffield United will go long with one last free-kick. Here it comes.. no they won't. The final whistle sounds with the ball high in the Manchester air.

Louis van Gaal's side are into round four. Just.

Chris Waddle
BBC Radio 5 live at Old Trafford

"Sheffield United have defended all game long but now they've gone behind they're just throwing bodies forward at a terrific tempo."

Elliot Turner: That goal takes nothing away from what has been a simply awful performance up front from Manchester United. #bbcfacup.

Tweet us on #bbcfootball.

Chris Waddle
BBC Radio 5 live at Old Trafford

"It's Dean Hammond at fault, you've got to give credit to Memphis Depay, since he's come on he's been very positive.

"Oh I'm looking at a replay and there's no contact. Or does he just catch him on the shin before he goes down?"

Image source, AP

Disaster for Sheffield United. Manchester United substitute Memphis Depay has been relatively bright and he beats John Brayford in the area, Dean Hammond is next in line and down goes the Dutchman. PENALTY GIVEN.

Is it though? It looks like a dive based on Depay's reaction but there is contact. What a chance to at least soften what will be some negative headlines for the home side.

Manchester United have had 72% possession, just one shot on target.

Conor Sammon signals his race is run, he waves his hands and will have to come off. The ex-Wigan striker fills his shirt with muscle, a big man.

Matt Done is on and we will have SIX ADDED MINUTES.

Cameron Borthwick-Jackson delivers from the left, cleared. Now Manchester United try the right, Matteo Darmian goes down, nothing given. Andreas Pereira, loses it, squeezed off the ball. 

Still they come but still with no conviction. Darmian again, to Pereira, Memphis Depay will shoot from range - right footed - roughly a foot wide.

Alan Green
BBC Radio 5 live at Old Trafford

Image source, Reuters

"A lot of Man Utd fans are heading to the exits, that's the faith they have in their team this season."