Utaka, 26, insisted: "I have studied a lot of videos of Cristiano in recent weeks. We play the same position and I need to come inside and score more like him. He has so much talent and I believe that by studying him it will help me to improve as a player.
"There's much more to come from me."
Utaka cost Pompey £7million from Rennes last summer.
He added: "I used to watch the FA Cup final back in Nigeria when I was a boy. It is the biggest game in football."