Anthony Elanga missed the crucial penalty as Middlesbrough won the penalty shootout 8-7 at Old Trafford and knocked Man United out of the FA Cup in the fourth round.
It seemed almost impossible to imagine after a first-half in which Jadon Sancho put United in front, Cristiano Ronaldo missed a penalty and the hosts created an incredible amount of chances in a dominant display.
They were made to pay for that wastefulness though, when Matt Crooks equalised in controversial circumstances after the break even though Duncan Watmore handled the ball in the build-up.
It remained 1-1 after 120 minutes and following 15 perfect penalties in the shootout, Elanga blazed his spot-kick over the bar to send United crashing out as they fell to an extraordinary cup upset.
Chris Wilder was adamant before the match that his side would go out to cause United problems, but they caused themselves real issues with less than 90 seconds on the clock.
A mix-up between Joe Lumley and Dael Fry resulted in the ball being fumbled straight into the path of Sancho 25 yards out. He sent a lovely clipped effort over the goalkeeper, but saw the ball bounce back off the bar and Bruno Fernandes couldn’t turn the rebound in.
It was a sign of things to come though, with Ronaldo getting an overhead kick away at goal but it was straight at Lumley.
With 20 minutes on the clock, Anfernee Dijksteel slipped and brought down Paul Pogba in the box for a stonewall penalty. There was no surprise over the decision but there was over the outcome - Ronaldo dragged his effort wide of the post.
Five minutes later though, United did have the lead. Sancho controlled Fernandes’ ball brilliantly, worked it onto his left foot and sent a strike into the far corner with the help of a slight deflection.
Fernandes blazed over from close-range himself, before Rashford went close with a number of efforts from range, as Middlesbrough were delighted to go into the break just one goal down.
It was more of the same at the start of the second-half, as Rashford missed a huge chance from a few yards out before Ronaldo hammered an effort into the side-netting, fooling half the ground into thinking he’d doubled the net.
But the visitors then equalised in controversial circumstances. Duncan Watmore controlled a ball into the box but it bounced up and hit his arm. He then lobbed it over Henderson and Crooks turned it into an empty net from a couple of yards out.
It seemed inevitable that VAR would rule the goal out, but it stood as officials deemed it to be accidental handball and Middlesbrough suddenly found themselves level.
United looked to have been gifted a goal, when Lumley’s dreadful ball out was pounced on by Fernandes. He had half an empty goal to aim at, but saw his effort bounce back off the post as the hosts’ frustrations mounted.
Anthony Elanga had two headers at goal in stoppage-time, one wide and one saved, as Middlesbrough held on to sent the match to extra-time.
It was a relatively uneventful first 15 minutes of extra-time, and while United pushed for the winner it was the visitors who nearly stole it. Paddy McNair headed the ball across the face of goal, Connolly flicked it towards goal but Henderson kept it out as the tie went to a penalty shootout.
Both sides kept their cool brilliantly from the spot, as the first 15 penalties were calmly sent past Hendeson and Lumley and no end to the shootout was in sight.
But Anthony Elanga stepped up knowing he had to score and sent his effort well over the bar, as Middlesbrough secured a famous FA Cup victory and Man United were left with another huge blow in what has been a painful season.
