Barcelona boss Xavi Hernandez said on Monday that his side must not miss out on a "very big opportunity" to move into the top four in the Spanish top-flight when they visit second-placed Sevilla on Tuesday.

"There are no doubts. They are a sensational team," Xavi said. "But there are three points at stake. Regardless of the difficulty of our opponents, we must add those three points in our favor. It's vital for us right now."

Barcelona sit seventh in the standings going into the game as Xavi attempts to rebuild his squad and have been relying heavily on younger members of the squad, especially 17-year-old midfielder Gavi.

Xavi said that it was essential that the club hang onto the talent coming through the ranks.

"If it comes to it we will all put in money from our own pockets," he said. "He (Gavi) is spectacular. We can't afford to lose these types of footballers. Neither Gavi nor Nico (Gonzalez), Abde (Ezzalzouli), Pedri or (Ronald) Araujo. They must be the foundations of the present and the future of the club."