Roberto Di Matteo says he is looking forward to working under Andre Villas-Boas next season, as well as returning to Stamford Bridge, where he spent six years as a player.
The popular Italian, who left his post as West Brom manager earlier in the year, was surprised when the call came to join the new-look technical team in West London.
"His call came a bit out of the blue to be honest," Di Matteo said. "It is mostly based on the fact that he likes my football philosophy and that is why he wants me to be part of his team.
"I think he likes to play football and be positive and attacking and over the years if you have seen a game or two of the teams I coached I think we played the same way.
"I liked my teams to try and win games rather than not lose, to build, to pass. He is going to be in charge of it and we are going to be working the way he thinks is the right way to be successful.”
He added: "It is obviously a challenge for me but I don't anticipate any problems.
"I have got experience of being a manager, I know what it is like, and I know what it is to be a coach, so I have a bit of both and I am there to support Andre and any of the staff, to give what it takes for us to be successful. That's the ultimate challenge."