Barcelona secured all three points in spectacular fashion courtesy of a stoppage-time winner from Lionel Messi, with the 3-2 victory seeing the reigning champions move to the top of La Liga on the head-to-head record.
Marcelo was caught high up the field when Barcelona broke for the winning goal, and the Brazilian left-back has conceded that he made "a mistake" which cost his side dearly.
"It was a mistake, it could happen to anyone but I fully accept the blame for the goal," Marcelo is quoted as saying by Marca. "We attacked at 2-2 because we felt that the further away the ball was from our goal, the better."
Real Madrid still have a game in hand over leaders Barcelona.