Roberto di Matteo says Chelsea need managerial stability.
Chelsea have gone through 13 managers (see below) in the time since Sir Alex Ferguson took charge of Manchester United in 1986.
Di Matteo, 40, reckons the new Premier League winners would have sacked Fergie last summer if they followed the Stamford Bridge approach.
"Chelsea had a rough patch in the winter with a few injuries," he said. "Most teams during a season have a bit of a bad run, maybe apart from the one team who is going to win it at the end.
"It would have been good for Ancelotti to stay and keep a bit of stability at the club. That would have been great. You see them and United - when they finish second, they don't revolutionise the whole club.
"Abramovich is the owner and we all have to respect what he does. But Manchester United could have sacked Sir Alex Ferguson many times before, yet that is how football is.
"You get the chance, you are successful, you stay. Sometimes even if you are successful - like Vicente Del Bosque at Real Madrid - it is part of the job. You know when you go into the job, you are going to be sacked at some point."
