Barca coach Luis Enrique has pushed Zubi to close a deal for the Croatia international as soon as he can.
The sports director flew to Seville yesterday accompanied by another Barca executive to open negotiations with Sevilla officials about a fee for the midfielder.
Rakitic's buyout clause is set at €40 million, but with just a year to run on his existing deal, Zubi insisted Barca would not go higher than €20 million.
The cash component could be driven down further with both clubs agreeing for Barca B striker Denis Suarez, formerly of Manchester City, to move to Sevilla in part exchange. Sevilla are insisting on an option to buy, while Barca are only interested in a straight loan.
Negotiations ran late into the night, but Sport says an announcement over an agreement could be made in the next 24 hours.
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