Manchester United boss Sir Alex Ferguson has sympathy for Roberto Mancini at Manchester City.
Mancini has had to deal with the likes of Carlos Tevez and Mario Balotelli this season.
Ferguson admits he can be driven to distraction by some players.
The Manchester United boss said: "Players can frustrate you, but it is a difficult industry we are in."
Asked if he had ever come close to striking one of his stars, Ferguson joked: "Strangle them maybe."