The Real Madrid legend says Barcelona's veteran midfielder remains an integral player for Vicente del Bosque's side ahead of next summer's World Cup.
The tournament is likely to be Xavi's last at international level following an extraordinary career that has seen him amass 130 caps and win one World Cup and two European Championships.
Though Xavi will be 34 by the time the tournament starts in June, former Spain captain Hierro is adamant the Barcelona star still has a big part to play for la Roja.
"He'll be in fantastic form for the World Cup. Xavi is a consummate professional, the best player in Spanish football. He represents a way of behaving, and a set of values," Hierro told Marca. "Spanish football and his club are both privileged to have him."
Xavi's recent performances have come under scrutiny following Barcelona's consecutive defeats to Ajax and Athletic Bilbao prior to its 4-1 win against minnows Cartagena in the Copa del Rey.
But despite having suffered a slight dip in form, Spain boss Vicente del Bosque insisted the experienced midfielder remains a big part of his plans.
"This is just a brief spell and you don't need to read anything else into it. We need to remain cautious. There's no reason to be pessimistic," he said. "As a player, Xavi is in great physical shape, and there's no reason why he should be experiencing problems. We are not conerned, and we have great confidence in him."
Spain remain one of the favorites to win the World Cup, despite being drawn in a tough group alongside Chile, Netherlands and Australia.