"It is clear that Peter is a better player now than when he came to Liverpool and we will have to be careful with him," said the boss.
"When we signed him people were talking about the money we paid for him, especially when he was waiting to score his first goal.
"But he showed his quality and he went on to do well for us and played many games for England also.
"It is clear that he is big, he is good in the air and he is a player with quality."