After Sunday's Euro2008 triumph, Xabi said: "It was a great strike from Fernando and on Sunday he showed he is the man who performs on the big nights.
"That goal has been key. He can be the best player in the world. He has all the qualities to get that award and he has a bright future in front of him.
"Winning against Germany is a massive step for him and for us. He is one of the candidates for World Player of the Year."
Arsenal midfielder Cesc Fabregas added: "Yes, Fernando can be the best in the world. This is about the Spanish team and not the individual performance but I told him the final would be his game and he would score - and he got that goal."