It's pretty obvious that Chelsea have a massive task ahead of them if they are to retain their Premier League title, but exactly how difficult a task have they made it for themselves?
The bad news for Chelsea fans - and good news for supporters of Manchester City - is that Jose Mourinho's side will have to break a Premier League record in order to win the league again.
In the Premier League's 23 year history the title has only been retained on seven occasions. Six of those successive titles were won by Manchester United, while one was claimed by Chelsea during Mourinho's first spell at the club.
To make matters even more daunting, the title have never been retained by a team that has made as bad a start as Chelsea have this season. The lowest points total after five games by a side that would hold onto their title, is the eight that Manchester United mustered in 2006-07 and again in 2007-08.
Chelsea have just four points and there's worse news in store for them. No side has ever suffered such a poor start and then gone on to win the Premier League. Furthermore, the only time a title-holder has had an equally poor start was back in 1995-96, when a Blackburn side that had seen Kenny Dalglish replaced by Ray Harford, finished seventh.
Take a look at the full record of Premier League title winners below.