Amid all the changes in status, personnel and management, the one enduring constant at Manchester City is their rampant inconsistency.
They have already taken that trait to new extremes this season, either winning in style or losing equally spectacularly. This was a performance from the far end of the scale in the latter category, all their early optimism evaporating as soon as things started to go against them.
David Connolly's two goals, the first from the penalty spot, deflated them completely and Wimbledon's extravagant winning margin completed by two Neil Shipperley goals in the second half did not flatter them unduly.
For the Wimbledon manager, Terry Burton, it was arguably the most satisfying result of his 18 months in charge. "I don't think any team comes here expecting to win 4-0," he said. "I knew it would be hard work, but we've got some good players and if we get the mixture right we've got a good chance."
Burton admitted that the manner of the first goal was a turning point. City had attacked from the start and a Dickson Etuhu shot could have been in the net if it had not hit Shaun Goater.
Wimbledon hit them on the rebound, the former City player, Michael Hughes, firing in a shot which Nicky Weaver should have held but instead merely pushed away. As Kevin Cooper chased the loose ball, he was brought down by Ali Benarbia and Connolly fired his kick past Weaver from the spot.
The confidence visibly drained away from City, who not only missed Paulo Wanchope up front, but also creaked ominously at the back whenever Wimbledon hit them on the break.
Connolly's second was a case in point. The impressive Jermaine Darlington did the initial damage, again down City's vulnerable right flank, and, when he whipped the ball over, Connolly one of the smallest men on the pitch headed home with ease.
City had plenty of possession but too many of their raids were ruined by the tendency of Darren Huckerby, Wanchope's replacement, to stray off-side. The introduction of the debutant, Alioune Toure, in place of the struggling Richard Dunne at half-time, gave Benarbia someone on the same wavelength, but the quality of the service into the box remained dire.
The nearest they came to a fightback was a header by Steve Howey from Danny Tiatto's cross that went just wide, but Wimbledon were by far the more dangerous side.
With seven minutes to play, Shipperley underlined their superiority, losing his marker, Simon Colosimo, as he cut in from the left and firing a shot inside Weaver's far post.
Many City fans were on their way out by then, the good days of this already startlingly up-and-down season a fading memory. They had safely reached the car parks when Shipperley struck again in injury time, receiving Cooper's pass and scoring at his leisure.
The City manager Kevin Keegan revealed that Wanchope needs knee surgery and will be out for six weeks. "We had 11 players underperforming today,'' he said. "We were lethargic and we went out there waiting for something to happen. I take my hat off to Wimbledon. They came here and played football, but if we play the way we did today, we're going to have a real struggle."
Manchester City 0 Wimbledon 4
Connolly pen 23, 35, Shipperley 83, 90
Half-time: 0-2 Attendance: 32,989Reuse content