Barcelona coach Tata Martino admits he fluffed his tactics for defeat at Real Sociedad.

Alex Song struggled in the 3-1 loss.

"Having three forwards implies that we wouldn't be playing with four midfielders. I thought that it was better to line up a double pivot, with Song," said Martino.

"Rotations are good when the results are positive."

When asked about his substitutions after Real had scored their third goal, the manager said that "we didn't have the necessity to rethink our approach and when we decided to make our first sub, they scored the 3-1."