“You are all idiots.” With those words, Sir Alex Ferguson swept the tape recorders off his desk and marched from the room. He thought the media’s treatment of Juan Sebastian Veron had been ignorant and unforgivable. A decade later, when sitting down to write his second volume of autobiography, Ferguson conceded the press might have had a point. Veron was a great and very expensive midfielder but he didn’t fit in anywhere at Manchester United.

At least Veron was never depicted as a cartoon donkey, which has been the fate of his sometime Argentina team-mate, Martin Demichelis, during his six tortured months at Manchester City. There are moments that define a season. When City were relegated to the third tier of English football, it was a balletic, almost unrepeatable own-goal from Jamie Pollock. In what once seemed would be a season of four trophies, it has turned on two tackles by Demichelis.

The first was on Lionel Messi which, since it produced a penalty and ensured his own dismissal, would have unravelled every pre-match calculation his manager, Manuel Pellegrini, had made before facing Barcelona.

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In a way, it was understandable. The world’s greatest footballer was clear on goal. The lunge at Marc-Antoine Fortuné, who is not even the greatest footballer in Wigan, was unforgivable. The penalty gave Wigan the belief to humble Manchester City in the FA Cup for the second successive year.

Long after the final whistle, in the Etihad’s concrete corridors, Samir Nasri was asked how he felt. “I don’t know. I cannot find the words because I am so disappointed.” He was not blaming his team-mate but everyone knew what had been lost. Demichelis was, nevertheless, a logical choice for Pellegrini to take to Manchester. The Chilean had never played or managed in England before and he would have wanted the reassurance of someone he knew.

When Bobby Robson first hired Jose Mourinho to be his assistant it was with the instruction: “I want to know what they are saying about me in the dressing room. If you lie to me, I’ll sack you.” Peter Taylor signed Junior Lewis eight times and when they were at Bradford they had a ‘Mr and Mrs’ contest to see how well they knew each other’s habits.

There were other, tactical reasons. Explaining why they were so attracted to each other, the Barcelona midfielder, Xavi Hernandez, said: “Pellegrini always wants to play football from the back and he has brought Demichelis to Manchester for that reason. He has been criticised but he can bring out the ball from the back.” Pellegrini has known Demichelis since they were together at River Plate a decade ago. After the manager had been fired by Real Madrid and was relaunching his career at Malaga, he signed Demichelis from Bayern on the same wages he was being paid in Munich. In his first season, he helped prevent Malaga’s relegation. In his second he helped qualify them for the Champions League.

There were compelling reasons for a third spell together, especially since City’s owners have proved reluctant to spend on the unglamorous area of defence. The back four of Zabaleta, Kompany, Nastasic and Clichy cost £30m – roughly what Manchester United paid for Rio Ferdinand more than 10 years ago. At £3.4m, Demichelis was cheap.

However, at 33 he was increasingly unreliable. The six points Manchester City have conceded to Chelsea are likely to be critical when the title is decided. The 2-1 defeat at Stamford Bridge was Demichelis’ debut.

At the Etihad, he was employed in Fernandinho’s absence as a holding midfielder, a job he had done successfully at Bayern Munich. But that had been nearly a decade ago and Demichelis proved utterly unable to stifle Eden Hazard. When Chelsea returned for the FA Cup, the task was given to Javi Garcia. City won easily.

That win opened up the prospect of an FA Cup final that was effectively ended by one tackle from a man few in the crowd would have picked. The model Evangelina Anderson once advised women living with footballers to “hire ugly” if they were looking for domestic help. Evangelina’s husband is Martin Demichelis and, should Manchester City finish the season with just the League Cup, many will think Pellegrini has hired very ugly indeed.

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