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"I am a bit disappointed that I'm back and Sir Alex is not there, as a manager. But I think David [Moyes] has conditions and protection but he club to do his job and do it well."
"Wenger is there, and I'm happy he is.
"[Manuel] Pellegrini at City is also a man with great experience. It's his first time here but I think he has maturity and quality to do a good job."
"Of course, there are still a few boys from my time, which is always good to go back and to see these people that gave absolutely everything for me.
"They know me, but it is important to tell you that there is no privileges for them."
"I think we have the same kind of vision. I'm happy to follow this philosophy he wants for the team. I'm happy to be back.
"At the same time I want something to be clear. I didn't choose to return to a comfortable position. I'm coming with a different perspective.
"I have more responsibility. I want to be respected for what I did in the past, but I want to be loved for what I can do from now."
"I'm back again because we are probably we are in the best moments of our careers.
"We are ready to work together again and in much better conditions than last time to succeed and bring what this club wants - stability.
"I think my relationship with the owner has to be private, not just with him but the board."
"I kept reading I was fired, I was sacked. That was not true. Many people didn't believe at the time that it was a mutual agreement, which we thought was best for me and the club.
"At he time it was a sad moment but I don't regret the decision because after that I went to Inter, where I probably had the best moment of my career.
After that I went to Madrid, where we still have the record of the best team in Spanish history."
"You can always do better. I want to believe it's possible. I always trust my work. I know the kind of mentality and ambition that people have.
"My career was built and based on success in every club. In every club I was able to reach success and trophies, and leave different kinds of legacy.
"My message to my players is 'work hard, work with quality, the club is much more important than ourselves, we are nobody compared with he club'."
"I am the happy one. Time flies. It looks like it was a couple of days ago [his last unveiling] but it was nine years ago.
"I am the same person, I have the same heart and I have the same kind of emotions related to my passion for football and my job but I am of course a different person. If I have to describe myself, I say I am a very happy person. It's the first time I arrive in a club where I am already loved."
@solonkasaita: "Mourinho will stay until his retirement"
@yikuzz: "I see him a huge disappointment during his 2nd reign at the club, I think he'll be out in a year and a few months"
@bills_sk: "He said it took him six mins to decide to come back. I am sure Abramovich will take equal amount to sack him again"
How long will Mourinho last at Chelsea?
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"I think his strength is his connection with the players," he said. "I wouldn't be surprised if he gets John Terry to be as good as he was some years ago again.
"Frank Lampard, he had a brilliant season last season, and he seems to be in great form, and with some new players he is going to bring in, I think that it smells like gold to me."
He is a good coach and will take Chelsea to the top," said the Frenchman.
“Though Mourinho did not fare too well at Madrid he is the right man for the Chelsea job and can push the club to win more titles.
"He has been there before and he knows the players, the fans, the management and of course the Premier League terrain so well, so it will not be a problem for him."
"You know you're at a busy press conference when there are photographers taking pictures of the photographers. This press room is almost full to the brim now, and the table where Jose Mourinho will sit is primed and ready.
"The interesting thing is there are only two chairs, which suggests the new boss will be accompanied only by Steve Atkins, the club's head of communications, rather than Bruce Buck or Ron Gourlay. Is this Chelsea giving Mourinho the freedom he craves right from the outset, or have I just drank too much free coffee?"
"With just under an hour to go until Jose Mourinho's entrance, the media room at Stamford Bridge is already buzzing with over a hundred people, and more are arriving with every passing minute. It is a reception which would overwhelm most managers, but you suspect this is just another day in the life of the Special One."