Benitez said: "Riise is playing well, but we still want to see more goals from him. He has more confidence and is going forward very effectively and now he has become an important player for us.
"We not only have a good winger, but a good defender who is excellent in the air and he can also shoot. He has given the squad something extra and he has given me more possibilities."
Riise himself has said he is happier under Rafa's new regime, and that this is helping his improved performances.
Riise added: "I felt I needed a new challenge and when the boss arrived he gave me a new style, and I feel fresher.
"I have played virtually every game since he arrived, and I must be happy with that. When a new manager comes in you do not always know what is going to happen but I have become more consistent and I am happier.
"This is my best all-round season and that is down to the manager and his staff. I am proving them right and scoring more goals than ever before," he concluded.