Gary's mistake against the club that loves to hate him was funny, freakish football melodrama at its theatrical best.
His gift of a goal to Shaun Goater brought a deserved City victory a step nearer and ensured the elder Neville will forever have an unwanted place in Blue folklore. It was every City fan's wet dream.
Beyond the gallows humour of the situation, though, others tried to take the criticism a step further and identify the Neville brothers as a symptom of the malaise currently bringing United to its knees. And you know what I thought when I read that and heard them bleating those opinions on the phone-ins? That's how we shall know them. That's how we can identify the prawn sandwich merchants and the neophytes and the know-nothings who have colonised our game.
Because, believe me, even if they didn't exactly distinguish themselves at Maine Road, the Nevilles aren't the villains of this or any other Manchester United story. They're the heroes. In fact, they're more than that. As the club heads South in the echelons of English football quicker than many of you may imagine, the Neville brothers represent United's last hope. They embody a spirit that is fast dying out in our game for the depressingly simple reason that they love the club they play for. Because they still care whether they win or lose. Because they feel ashamed when they let their side down.
If you want to know, Gary Neville went straight home after the game on Saturday afternoon and didn't leave his house until Monday morning.
He didn't read a newspaper. He didn't turn on his television set. He felt angry about the way he and the rest of the United team had played. When he did finally reach for the remote control, it was only to pore over a re-run of the horror that had been visited upon him at Maine Road so he might at least learn from it.
I'm not saying any of that necessarily makes him a good player. It doesn't. But it's a start. And it sets him apart from a raft of his team-mates.
Gary and Phil Neville feel responsible for what is happening at Old Trafford in these difficult days when decline is at the team's shoulder. And with that responsibility comes a desperate desire to put things right. Do you think Juan Sebastian Veron feels that desire? Or Laurent Blanc? Or Fabien Barthez? No, I thought not.
Those last three are helping to turn United into a team that resembles the Chelsea side of a few years back. Who could get themselves up for a big game in the Champions League when they were playing against some of their old buddies from Serie A. But couldn't hack it when Darren Huckerby was running at them on a cold Saturday afternoon at Highfield Road.
This United team doesn't like its bread and butter any more. It chokes on it. And asks for another slice of cake.
So ask me whether I'd rather have Phil Neville or Laurent Blanc in my Manchester United team now when their backs are against the wall and I'd have Phil Neville 100 times out of 100. Ask me to choose between Gary Neville and Veron or Barthez and I'd choose Gary. One hundred times out of 100.