Good afternoon! Chelsea face a tricky match against local rivals Arsenal this weekend, and manager Jose Mourinho is due to speak to the media ahead of the match shortly.

In-form striker Diego Costa has insisted that he will be fit for the match, despite being involved in the Champions League earlier this week. It's been a good week for the summer signing, who was named in the Spain squad, and voted PFA player of the month.

Costa's arrival has helped Chelsea make a superb start to the season. The Blues are unbeaten, with their only dropped points coming in a 1-1 draw at champions Manchester City last month. Their results have left them three points clear at the top of the table.

There's a tricky run of matches coming up for Chelsea. As well as the visit of Arsenal this weekend, Mourinho's side will face trips to Liverpool and Manchester United in the coming weeks, as well as London derbies against QPR and Crystal Palace.

This will be the 12th time that Mourinho has prepared a team to face Arsene Wenger's side. Mourinho is unbeaten in his previous 11 meetings against Arsenal, which have included six victories.

Mourinho has just arrived at the club's Cobham training ground to speak to the press, so let's see what he has to say this week...

Firstly, Mourinho is asked about Diego Costa. The manager confirms that the striker will play against Arsenal, and that he is not surprised by his call-up to the Spanish national side.

Still on Costa, Mourinho adds: "If he has a problem playing against Arsenal, he has a problem playing for Chelsea. The Champions League match was crucial for us so I had to go with everybody. Arsenal is also an important match. He plays against Arsenal, what happens after that is not my responsibility."

Arsene Wenger has already said that he is seeking revenge for the 6-0 defeat that his side suffered last year. Mourinho admits: "The 6-0 is once every 50 years. It is something that happens occasionally."

When asked about his opposite number, Mourinho tells reporters: "Me against Arsene Wenger, I never had the pleasure to play against him one-on-one, it is always between Chelsea and Arsenal. That doesn't play an important part of Sunday's game."

New Chelsea signing Cesc Fabregas will face his former club for the first time since returning to England. Mourinho says: "If 40,000 Blues fan want, nobody will listen to 3,000 red fans. It depends on the club culture. You could see the Chelsea fans with Lampard. It depends. Fabregas was made at Arsenal. Every game, no exception, [Fabregas] is playing well. I couldn't be happier with the moment he decided to join. He's our player, that's what matters."

When asked about the prospect of facing Arsenal, Mourinho replies: "A difficult match. It doesn't matter what they try to do, they can have many different approaches. I always expect [to win] every game. Nothing change in relation to that."

On the subject of injuries, Mourinho confirms that Ramires and Didier Drogba will both miss Sunday's match.

Mourinho believes that his players will cope well with the derby atmosphere: "The players are more than ready for that. I have a meeting with them, not a motivational meeting, just about football, never about the emotional side."

Cesar Azpilicueta agreed a new contract extension earlier this week. Mourinho says that he's an important player for the team: "He's a fantastic professional. A fantastic team player. The club gave him a new contract because he's the kind of boy you want to keep."

That's all from Mourinho for now, but be sure to join us again on Sunday to find out if Chelsea can maintain their unbeaten record. Until then, thanks for joining me this afternoon, goodbye.