"Seven points are an important advantage but it is too soon to talk of titles," Schuster said after the game. "The situation is good at present but you don't win things until the end."
Brazilian midfielder Julio Baptista scored the game's only goal in the 36th minute. Barca played poorly, and star Ronaldinho, who returned to the starting lineup, was whistled by Barca fans.
Barca coach Frank Rijkaard tried to look on the bright side.
"My players showed a good attitude on the field and in the locker room," he said, "but we have to keep looking forward. We have to believe in our chances. The fact we were in the game until the last moment shows we continued fight to the end."
Regarding Ronaldinho, Rijkaard said: "It was clear this wasn't one of his best games, the same as his colleagues, but he showed good commitment."