That is according to Manchester City fan Noel Gallagher, who was working as a pundit for Sky Sports on the game.
City took the lead at Old Trafford in the 43rd minute, with David Silva finishing from close range.
Marcus Rashford equalised in added time for United, to the delight of Neville.
Gallagher admits he was disappointed that his side were not leading at half time.
But he said it was a good insight into how Gary Neville behaves while United are playing.
“Yeah (I’m slightly disappointed),” Gallagher said.
“If we go in 1-0 up it’s a different game second half.
“But it’s been fascinating watching this fella here having a mental breakdown up until the goal.
“If I knew when I’m watching from home that this is what he’s like when he’s watching Manchester United, it’s going to make it all the more enjoyable for me this season I think.
“He was having a bad day up until the goal, he was having a bad day.”
Gallagher was impressed by the first-half showing of Manchester City goalscorer Silva and Kevin De Bruyne.
“Always, he’s the main man,” Gallagher said of the Spaniard.
“When you’ve got him and De Bruyne backing him up, they’re difficult to get the ball off of.”
City went on to win the game 2-1 thanks to a second-half goal from Nicolas Otamendi.