However, the goal-line technology watch being worn by referee Michael Oliver — which is supposed to alert the whistleblower when the ball crosses the line — did not go off and Villa were spared.
Hawk-Eye Innovations, in charge of the goal-line technology, released a statement after the match saying the officials weren't alerted to the ball crossing the line because the cameras inside the stadium were "significantly occluded by the goalkeeper, defender and goalpost".
"This level of occlusion has never been seen before in over 9000 matches that Hawk-Eye Goal Line Technology system has been in operation," the statement read.
"Hawk-Eye unreservedly apologises to the Premier League, Sheffield United and everyone affected by this incident."
Sheffield United coach Chris Wilder was fuming.
"I think the goalkeeper was in the Holte End when he caught it — or dragged it back. My issue is obviously one of frustration," he said.
"Seven cameras haven't picked it up — the most technical league in the world — everything we see at every angle and it hasn't seen a goal. That is disappointing from our point of view.
"We went to Tottenham last year, John Lundstram's big toe was offside and I was hanging around at White Hart Lane in the pouring rain for 10 minutes waiting for a decision. I don't understand why I can't wait 10 minutes in Birmingham.
"The statement has come out and it is unprecedented, unbelievable. I did have a laugh and joke beforehand that we have had some poor decisions go against us and I said I wouldn't bet against one going against us this evening."
Former football star Stan Collymore said on Twitter it "should have been a Sheffield United goal" and the ball was a "country mile over" the line.
In the day's other match, Manchester City beat Arsenal 3-0.
