Harry Redknapp believes Mark Clattenburg made 'one of the worst decisions ever' in allowing Nani's goal to stand on Saturday.
Nani scored after Tottenham keeper Huerelho Gomes believed a free-kick had been awarded for a clear handball by the Manchester United winger.
Nani struck home, giving United a 2-0 lead and sealing their win.
However, Clattenburg did not give the free kick against Nani, even after consultation with his linesman, and Redknapp was furious at the decision.
Writing in his column for The Sun, Redknapp said: 'Mark Clattenburg is responsible for one of the worst refereeing decisions EVER. And each time I watch it, it gets worse...
'I like Mark Clattenburg...but he knows he's cocked this one up...I know he has told people he should have blown his whistle and given a free-kick against Nani for handball.
'He has ruined my weekend - and the same applies to thousands of Spurs fans here and abroad. You spend so much time preparing for a big game like Manchester United away. Old Trafford is a hard enough place to go without simple decisions like this one going against you...
'I would never have dreamed in a million years we would be undone in the way we were... by one of the worst refereeing decisions of all time.
Despite previously saying it was not a decisive incident for the result of the game, Redknapp pointed the finger at the referee: 'Yes, I know we were losing 1-0 at the time. But who knows what could have happened in the final few minutes and then the time added on?
Redknapp blamed Clattenburg for the confusion before the goal: 'Even now I still can't get my head round it. As far as my goalkeeper Heurelho Gomes was concerned - and every one of my players - it was a free-kick.
'If any of my team had thought otherwise, they would have been shouting at Gomes: "Kick the ball away!" The referee had his hands by his side and was just shrugging his shoulders. Usually, if the ball's in play, the ref will shout to let you know.
'If, for instance, the ref thinks there's a backpass that wasn't deliberate, he'll make sure you know in no uncertain terms...All the referee had to do was blow his whistle and it resolves the situation.
'There was no advantage to my team, the ball was in our penalty area. How could that be advantageous? It wasn't like we were bombing forward into their half with a great chance of scoring an equaliser. No one could believe the ref played on.
'I was absolutely gobsmacked... and I still am. After a lifetime in the game, not many things still shock me. But this one did.'
And the Spurs boss is not expecting an apology: 'One thing you can be certain of is that the referees will stick together on this. But it's not right. They know a real mess was made of this situation. Wouldn't it be great if they actually held their hands up and admitted Clattenburg got it wrong?
'Don't hold your breath - you might keel over. I was listening to the radio yesterday when the former ref Alan Wiley came on. He tried to explain the situation but all he did was make excuses. I don't care what anybody says, it wasn't right in the spirit of the law.'
He makes it sound like the decision had a major impact on the game