The Blaugrana official stated that it is only a matter of time before the Argentine pens a new deal, while doubting Iker Casillas' chances of winning the Ballon d'Or
Spanish sources have claimed in recent days that the Argentine midfielder, who has mostly been deployed as a centre-back at Camp Nou, is set to extend his contract with the Catalan giants.
"Negotiations over Mascherano's renewal are at a very advanced stage," Zubizarreta said at a press conference.
The 50-year-old is currently working on renewing the deals of many of the squad's players, but insisted there are no developments regarding Carles Puyol and Adriano.
"I have spoken with Adriano's agent, but we have not yet talked about contractual issues. We told him that we are happy with the player's performances last season.
"Puyol's case goes beyond a simple contract renewal, for his history at the club and what he means to it.
"Once this week is over, we will sit down with him to find out what he thinks, what he wants and reach an agreement."
Zubizarreta went on to cast doubt over Iker Casillas' chances of winning the Ballon d'Or after helping Spain win their second consecutive Euro title.
"Ever since Jose Angel Iribar was not given the Ballon d'Or, I have ruled out the possibility of a goalkeeper winning the award," he explained.