Neil Humphreys: Are City invincible or beatable?
It might take bad luck, a depleted line-up or rivals seeking revenge for Guardiola's men to lose a game
The English Premier League title race is practically over before Christmas.
Manchester City can make preparations for their open-top bus parade. Everyone else is playing for second place.
But can the untouchables remain unbeatable for the rest of the season? Here's a look for potential banana skins that could slip up the City slickers.
DEFENCE NOT INVINCIBLE
As Manchester United launched hopeless balls towards the box, Vincent Kompany's lack of fitness wasn't really exposed in the derby.
But the centre back went off at half-time and didn't return.
Pep Guardiola's exuberance after the victory deserted him only once - when he discussed his frustration with Kompany.
He can't keep the Manchester City defender fit. After 18 months of injury setbacks, the 31-year-old Belgian can no longer be relied upon to protect the back four.
John Stones is already out and the hectic festive schedule looms large.
West Ham showed that City are vulnerable to smart crosses across the six-yard box, something that United failed to produce.
On the rare occasions when the Red Devils did muster a positive attacking move, only Ederson denied the hosts an undeserved point.
Two injured centre backs and a central midfielder covering at left back (Fabian Delph) doesn't quite match Arsenal's wall of resistance during their invincible run in 2003-2004.
City will concede goals against more adventurous opponents. The tricky part is making sure they concede more goals than they score.
ROTATING COMES WITH RISK
Guardiola has cleared his biggest psychological barrier. Beating United buys bragging rights and breathing space.
An 11-point gap ensures a degree of freedom in team selections.
City face seven fixtures in less than three weeks in grim conditions.
After the United victory, however, there's not quite the same sense of urgency.
City do not need to win them all and the temptation to rest David Silva and Kevin de Bruyne must be overwhelming, with bigger fish to fry in the New Year.
The duo played illusionists against United, fooling the audience into believing City had extra men on the field.
Their control of both their opponents and the game's tempo was absolute.
So an injury against the likes of Swansea on Thursday morning (Singapore time) or Bournemouth on Dec 23 would be both catastrophic and idiotic.
City can nurse an 11-point lead in the EPL without them. But City may not prevail in the Champions League without them. So Guardiola will rest and rotate, quite radically, in the coming weeks, just as he did against Shakhtar Donetsk - and City lost. The Spaniard wasn't particularly bothered by that defeat and a loss over the festive period wouldn't be the end of his world either. Unbeaten runs please stats geeks. Guardiola is interested only in silverware.
RIVALS OUT FOR REVENGE
Looking at City's fixture list, only a few stand out as potential banana skins. In the middle of an intense Christmas period, Guardiola's men host Tottenham on Dec 16. Spurs represent one of the few sides capable of seriously testing City, thanks to their firepower. In the Manchester Derby, United had Romelu Lukaku and a long-ball mantra. Spurs have a more positive approach and Harry Kane.
They knocked five past Stoke at the weekend. Along with City, they are one of only three teams capable of scoring from all angles, thanks to a regular and varied goal supply. Liverpool are the other.
The Reds host City on Jan 14, after an FA Cup weekend of rotations. Despite their defensive limitations, Liverpool's fabulous front four still represent the EPL's greatest hope of outscoring Guardiola's sharpshooters.
Should they fail, City's only other serious opponent will be complacency. In March and April, they take on Chelsea, United and Tottenham. The league title should be done and dusted by then and it's hard to play for pride indefinitely.
So just picture the scene. On April 7, United head to the Etihad, where City are not only champions-elect, but undefeated champions-elect.
The script could be devilishly subversive. And United have a track record, having defeated Arsenal's Invincibles back in 2004. Stopping City would be even sweeter. To do that, however, Mourinho must first take off the handbrake.
BAD LUCK OR A BAD REF
Here's a final, depressing fact to ponder. City are still enjoying a 100 per cent winning record - when it's 11 against 11. Their only dropped points came against Everton in August, when they drew 1-1.
But Kyle Walker was sent off. So perhaps the man in black will play the white knight. A poor referee, a dodgy red card or a soft penalty might prove to be the only way to stop City in a long, unpredictable season. It sounds desperate. But right now, it's easier to clutch straws than it is to catch Guardiola's men.
Ugly end to Manchester Derby as reports of 20-man brawl emerge
Manchester United manager Jose Mourinho became involved in a physical confrontation with Manchester City's players after complaining about their post-derby celebrations, according to British media reports yesterday morning (Singapore time).
The Daily Mail and Daily Telegraph said Mourinho went to City's changing room following United's 2-1 defeat at Old Trafford because he felt their noisy celebrations were disrespectful.
The newspapers reported Mourinho had a verbal altercation with City goalkeeper Ederson before having water and milk thrown at him by City's players and being hit on the head with a plastic bottle.
During the fracas, City assistant coach Mikel Arteta was also allegedly hit in the head by a thrown bottle and suffered a bad cut.
The Guardian reported that his eyebrow was split open and he bled profusely. He was pictured covering his face while arriving for training in the morning after the game.
The Mail said United's security had to break up a brawl involving 20 players and staff members from both clubs, which was said to have occurred near the Old Trafford tunnel.
Referee Michael Oliver did not witness the scenes so the FA has not received a report on the matter from him but it has given the clubs until Wednesday to reply to a request for observations following the incident.
Former Premier League referee Graham Poll said in The Mail that the incident means "extra paperwork" for Oliver, whether or not he saw the incident. He said: "Any violent conduct by players or substitutes will be reported as red cards and attract similar punishments."
The reports of the Mourinho incident brought to mind the "Battle of the Buffet" that erupted after United beat Arsenal in October 2004, when Arsenal midfielder Cesc Fabregas threw pizza at United manager Alex Ferguson. - WIRE SERVICES
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