Paul Hayward: 'Man United going nowhere without a commanding centre-back pairing'
Shocking stat alert: the last time Manchester United conceded more than 20 goals after 12 league games was in 1966, a year well known to Bobby Charlton, who laid a wreath on the pitch with Mike Summerbee before this game.
Jose Mourinho's worst nightmare is a porous team, a wonky defence, a hefty goals-conceded column. It goes against everything he stands for: stubbornness, compactness, parsimony around your own net.
Mourinho's starting point as a manager is to ban the opposition from scoring. Then you put the other bits on top. But with 21 goals given away in 12 league outings, and a goal difference of minus-one, the apparent rebirth at Juventus in midweek felt like an illusion here. United are a mid-table team primarily because they are too easy to score against.
One clean sheet in a dozen games is the polar opposite of a Mourinho side. We can be sure he is coaching the daylights out of his back-four (and midfielders), so the problem must be one of quality, of individual ability, after a long phase in which United have failed to sign top-class defenders.
Where is their Virgil van Dijk, their Aymeric Laporte, their Toby Alderweireld? Centre-back pairings - integral to United's success since the early 1990s - have become a game of pick and hope, of guess and rotation.
Even with the proviso that City can slash gaps in any team, and bamboozle them with how they move the ball, three more breaches of United's net were in line with a pattern Mourinho has been labouring against all season.
The United manager's 300th Premier League game proved what people have been saying since Rio Ferdinand and Nemanja Vidic left the scene. Chris Smalling. Victor Lindelof, Marcos Rojo and Eric Bailly are simply not at that level, while Ashley Young, a fine pro, is not a conventional full-back.
Luke Shaw is sharp again at left-back but overall United's backline has a quality deficit, even with Ander Herrera scurrying around in front of it and Nemanja Matic coasting around in sentry mode.
Everyone knows Mourinho wanted to buy centre-backs this summer. Asked about that, he refused to deny it, but also stuck up for Lindelof and Smalling, or 'Smiling' as Pep Guardiola referred to him.
"But I don't think it was the game to touch on that point," Mourinho replied to the centre-back question. "I think Victor and Chris had a positive performance."
Neither was particularly bad, just at a level below what you would call commanding. That word is the most pertinent. United lack commanding defenders. The backline lacks authority, power, certainty.
Mourinho, though, protected his defenders and instead blamed fatigue from the Juventus trip. He also fell back on United's growing ability to fight back in games, to keep going.
Alex Ferguson, who was here, used to tap his watch at the end of games not as a timekeeping service to referees but to instil fear in the opposition. The message was: this is where United always score. In those days, United would be pouring forward with hellfire in their eyes. They scored as an affirmation of the team's pedigree. For 20 years opponents lived in fear of what United would do late in games.
Mourinho's United are comeback specialists too, but by bump and grind, rather than irresistible play.
In Turin, during a potentially season-changing victory over Juventus, they scored in the 86th and 89th minutes. The old songs are the best. But the familiar dirge returned four days later. United were sliced open by City in the opening exchanges and conceded after 12 minutes.
Goals for David Silva and Sergio Aguero left United with their worst defensive record after 12 games for 17 years. Then, City's third, four minutes from time, sent United spinning back to England's World Cup winning year.
Anthony Martial's penalty after 58 minutes had put United back in the game but City have a spare sack of goals they can always delve into when the opposition start to get cheeky.
"The fight until the end is something we're building, and we're not going to lose that," Mourinho said.
But he over-played the strength of the United counter-surge. Best of all was him claiming that Paul Pogba's injury removed Marouane Fellaini as a late-game weapon City would surely have succumbed to.
He said: "To bring a fresh Fellaini to the pitch, they would have been in big trouble. It's one thing to bring a fresh Fellaini, it's another to play him from the beginning."
He was not going to discuss defensive frailties.
"You can go for stats," Mourinho said. "That's the way people who don't understand football analyse football. I don't go for stats. I go for what I saw and felt in the game. And the game was there until minute 85.
"I consider the performance of my team a performance with mistakes. It's different to a bad performance. We made mistakes, we were punished for mistakes."
The echo of 1966 is alarming for United's supporters, but there is a brighter angle to it. The club won the league that season (1966-67). But they are 250/1 with some bookmakers to do so this time round. (© Daily Telegraph, London)