The youngster has been seen at Barca as a potential successor for captain Sergi Busquets.
And ahead of their Copa del Rey clash, Xavi said: "He is a more physical and faster player than Busi, who is technically better. But not only Zubimendi, all the midfield players. A great team visits us. Zubimendi is a great footballer.
"We work in the same way in grassroots football. But La Real works very well with the academy.
"We lack a defensive pivot who is the future of Busquets."