"Why not as a player?" quizzed Van Nistelrooy. "If he was to come back, he could train with us, even if he didn't play.
"When I first signed for Madrid, he still had a year on his contract and then I found out he was retiring and thought 'gee whiz, I'm not going to get to play with Zidane'.
"For that reason, I say if he is to return to Real then he MUST train with the players!"
Van Nistelrooy added: "I do not know him personally, but everyone in the dressing room says he is a great person and I really want to get to know him."