The Argentina international agreed an extended contract with the club to June 2018 before heading to Brazil to represent his country at the World Cup, though rumours of a return to Liverpool and move to Napoli continued to surface.
However, after recently returning to training, the defensive midfielder has set a date to pen his new contract and extend his stay with the club by another four years.
A club statement read: "FC Barcelona have announced that Javier Mascherano will sign an improved and extended contract on Tuesday, August 26 that will see him stay at the club until June 30, 2018.
"This extension was agreed and announced just before the start of the World Cup in Brazil, where Mascherano was playing for Argentina. The new contract includes a buyout clause set at €100 million.
"Javier Mascherano rejoined the first team during the first week of August along with the other players whose national teams made it to the semi-finals of the World Cup and is expected to play his first game of the season at Monday night’s Joan Gamper Trophy [against Leon]."
