"Pepe is the best in the Premier League for me. He is the number one," said Benitez.
"He is good with the ball, good in possession and he is good at organising the defenders and so he can help them. He can also start the counter-attacks. He is the complete goalkeeper.
"He is very important for us in attacking terms. He is a threat to defences because when you have Torres and Pepe together you know as a defender you cannot be watching the game. Pepe can give assists.
"He works hard on his kicking and you can see how good he is. He has a very good mentality and is always joking so his teammates are happy with him.
"When you talk about goalkeepers their job has changed. Before it was just being in the six-yard box saving shots. Now they have to be reading the game and the goalkeeper is now the sweeper.
"It is not easy for him with Spain because Casillas is doing so well, but for the level Pepe is he could play for any other country.
"A goalkeeper can win you the title definitely. When you are attacking all the time, he might have one save to make and that can be the difference.
"The keeper is really a key player, think of Schmeichel and Van der Sar last season for Manchester United."