Casillas is struggling for playing time at Porto at the moment and does not seem to be in the plans of the Portuguese club.
One suspects that Porto would be more than happy to get the Spaniard off their books in the January transfer window given that he reportedly earns £95,000 per week.
While Newcastle, who won promotion from the Championship to the Premier League at the end of last season, may not be willing to or be able to afford to meet the Spain and Madrid legend’s wages, one thing is for sure - he would get along well with Benitez, who rates him highly.
Benitez worked with Casillas for a very brief period of time when he was the head coach of Madrid, and the former Liverpool and Chelsea boss rates him highly.
Following the 36-year-old departure from Los Blancos to Porto in the summer of 2015, the current Newcastle manager heaped praise on him.
“Iker is a living legend at Real Madrid and the best goalkeeper in the club's history,” AS quoted Benitez as saying about Casillas in July 2015. “We all know how important he has always been.
“He has made the decision to leave and to go to another club. As coach, I have to respect that decision and wish him the very best of luck.
“I believe that he will remain in the hearts of all Madridistas and from here on I wish him success, I hope that everything goes really well for him and that he enjoys being at a great club and in a great city. There's not much more to say, except to express my respect and admiration for him.”
It is clear that Benitez has respect and admiration for Casillas, and one suspects that the pair would work well together at Newcastle should a move happen.