"I've known Christian for a little while now, and I saw him when we met up with the national team recently," Essien tells the official Chelsea website. "He's a level-headed boy, a very good player and hopefully he will do well for Chelsea in the future.
"He is a winger who plays mainly on the right-hand side although he is left-footed, so he likes to cut inside, and he is quite quick as well. He is only young but already you can see he has an eye for goal.
"For a young player he is already quite experienced because he played a few matches for Porto in last season's Champions League. The loan move should be good for him as hopefully it will allow him to play more regular first team football."
For the big stories and the banter follow us on Twitter: @tribalfootball