Chris Wilder and Ralf Rangnick on Cup controversy between Manchester United and Middlesbrough

United missed chance after chance in the opening hour - including a missed spot-kick from Cristiano Ronaldo - and had only Jadon Sancho's first goal on home soil to show for their dominance.

Boro dug in and improved markedly after the hour mark and drew level in dramatic fashion.

Substitute Duncan Watmore clearly handled a throughball from Isaiah Jones, but was a big beneficiary of the accidental handball rule.

The goal was allowed to stand due to changes in handball laws this season. Watmore was not the player who scored with Matt Crooks turning in his lob over Dean Henderson into an unguarded goal.

As United's performance levels dipped, Boro took heart and secured extra-time and then penalties.

A total of fifteen spot-kicks were all converted before Anthony Elanga ballooned his effort into the Stretford End as Boro became the first EFL side to win in the Cup at Old Trafford since Leeds United in January 2010.

The win also emulated their wins on penalties in the EFL Cup at Old Trafford in 2016, while Wilder triumphed at the famous venue for the second successive season following former club Sheffield United's win there last season.

Admitting that he thought Crooks's goal would be chalked off, Wilder said: "The FA Cup is alive and kicking, especially in Middlesbrough. I told the players it was all about making memories.

"We rode our luck and took our chances. The decisions that are made through VAR have changed since I left the Premier League - I thought straight away it was handball. I thought it would be chalked out and delighted it wasn't."

United's record of never winning a penalty shoot-out in the FA Cup continued, with interim boss Ralf Rangnick admitting to being disappointed by the failure to rule out Boro's goal.

He said: "I am Incredibly disappointed, we should have won and killed off the game in the first half. Crossbar, post, missed penalty and numerous chances. It should have been 2-0 or 3-0.

"We conceded a goal which I don't understand why it stood. He controlled it with his hand.

"In the moment when they scored, it was clear that VAR would not allow this goal to stand. We were not well positioned in that moment, too open and allowed them the counter, we should have won the game.

"Anthony Elanga, anyone can imagine how he feels, he is shattered and absolutely disappointed."