Houllier said: "I feel he is the missing link for us. He can score, he can be the link between the midfield and the strikers. He can create and he can finish, he is a perfect offensive midfield player. These days in football a player has to do practically everything, just think of Thierry Henry. He defends, attacks and has creative skill.
"That's what I see in Harry. I admire him as a team player and he can thrive here. I have always been a great admirer of Harry, of his talent and ability. When I first arrived in England he was one player I instantly liked. When Leeds were in the Champions League I used to go to watch many of their matches and Harry was outstanding. I'm very, very happy to have him. He will play an important part in our future."
