Proclamations that City are suddenly champions-in-waiting seem somewhat premature. With 22 games to play, Arsenal are still very much in contention. Lest we forget, Wenger's team currently sit top of the Premier League table.
However, there were alarming signs for Arsenal in this game. This performance was littered with the kind of calamitous defending that Arsenal fans thought their team had banished from their game.
Arsenal went into the game with the league's best defensive record. That record was obliterated by a six-goal blitz from City.
Manchester City are an awesome attacking force. Under Manuel Pellegrini, they are finally playing with the attacking verve you'd expect from a club with billion-pound backing.
Arsenal needed to produce their best defensive performance of the season today. Instead, they produced their worst.
Wenger was able to call on four of his first-choice back five. Kieran Gibbs was absent from the matchday squad with an as yet unexplained injury, but Bacary Sagna returned to replace the inexperienced Carl Jenkinson.
However, this was not the watertight unit Arsenal fans have become accustomed to seeing in 2013/14. Arsenal’s performance was blighted by individual errors, such as Laurent Koscielny’s failure to track Sergio Aguero at the corner which gave City their opening goal.
It would be wrong to blame solely the back four. Several of the goals Arsenal conceded came as a consequence of poor midfield play. For City’s second goal, Yaya Toure was allowed too much room in midfield. Given time and space, he played in Pablo Zabaleta to cross for Alvaro Negredo to score.
Wenger: "We made too many mistakes. Our strength until now was defensive discipline and that went [today]." Says "easy mistakes" to blame.— Julian Harris (@attacktheball) December 14, 2013
Similarly, City’s third goal was the consequence of a poor pass from Mesut Ozil and an ill-timed lack of control from Mathieu Flamini. By the time Pellegrini’s team added their fifth and sixth strikes, Flamini had been withdrawn and Arsenal had no defensive midfield cover of any kind.
With Flamini off the field, Jack Wilshere was asking to fill the holding role as Arsenal chased the game. Wilshere, who had a tough time all afternoon, was overrun and out-thought by the likes of Samir Nasri, Toure and David Silva.
Arsene Wenger might now be regretting his decision to leave out the disciplined Mikel Arteta. While Arteta had not had his best game against either Everton or Napoli, he might have helped Arsenal do a better job keeping the ball better in their own half instead of conceding possession and inviting pressure.
Arsene Wenger and his coaching staff will doubtless point to fatigue. The Gunners faced a harrowing schedule of three difficult games inside a week. However, questions will be asked: Can a side that ships six to a supposed rival really go on to win the Premier League?
Perhaps surprisingly, there is a precedent.
In November 1990, Arsenal conceded six goals against Manchester United, with a youthful Lee Sharpe grabbing a hat-trick. Come May 1991, the Gunners were champions.
There is hope yet. Arsenal have nine days to rest weary limbs, restore hurt pride and concentrate their minds. In their next game, they face another title challenger: Jose Mourinho’s Chelsea.
It won't be easy. Laurent Koscielny picked up a knee injury in this game that could rule him out of the crucial Christmas period. Plenty of work will have to be done on the training ground to return Arsenal to the solid unit they had looked prior to their visit to the Etihad.
If Arsenal can get that miserly defence back, then their title dreams will seem plausible once more.
Arsene Wenger’s first victory over the Portuguese would be the perfect remedy for their Manchester misery.
James McNicholas is Bleacher Report's lead Arsenal correspondent and will be following the club from a London base throughout the 2013/14 season. Follow him on Twitter here.