Gary Neville claims Manchester United missed Michael Carrick in their last two defeats against Chelsea and Everton.
The 20-time English champions were high on confidence prior to the clash against the Premier League leaders, as they managed victories over Tottenham Hotspur, Liverpool and Manchester City.
However, Louis van Gaal's side suffered a 1-0 defeat at the hands of Chelsea, which was followed by a 3-0 loss against Everton at Goodison Park. Without Carrick, the Old Trafford club have won only 37.5% of their matches.
The former Red Devils defender says Carrick has been the key player for United and claims their latest defeats in his absence is not a coincidence.
"When Michael Carrick doesn't play, their record without him shows he is missed," Neville told Sky Sports.
"It is not just the control and composure, but it is his forward passes, he just moves the ball forward into good areas quickly."
"When United won the ball back today they didn't get the ball forward quick enough. Michael Carrick does that. Even if it is only a 10-yard pass, he gets the move moving in the right way. They miss him badly, they really do. It is no coincidence they have lost the last two games without him."
The former Barcelona and Bayern Munich manager slammed his players for their lack of aggression in United's latest defeat to Everton. Neville echoed Van Gaal's comments and as he suggested it was the worst performance of his former club in the last two months.
"United were toothless, and that is being kind. I didn't really see them try and dribble past a player, make any forward runs. At times they were not getting enough men in the box and the final pass was poor," the former England international said.
"It is the worst I have seen United play for five or six weeks. They have been playing so well. Even in defeat at Stamford Bridge last week they played really well."
"Today it wasn't there. It was Everton who had the cutting edge. It was through Lennon, Lukaku and Mirallas when he came on who looked the ones most dangerous to break through either defence," Neville stressed.