Carlo Ancelotti blamed Real Madrid's draw with Valladolid on mental fatigue but insisted La Liga's title race is not over.
Despite Cristiano Ronaldo going off injured early on, Real went ahead through Sergio Ramos, but a late header from substitute Humberto Osorio ensured the spoils were shared.
The result marked Real's second successive draw, which Ancelotti attributes to the club having played 10 matches since the start of April as it bids to conquer Spain and the UEFA Champions League.
"Physically we are not tired," Ancelotti said. "But mental tiredness cost us. After such a Champions League semifinal it's not easy to recover quickly at such an important tie of the season. We were in control for 70 minutes, but we lost control, sat back and conceded a goal from a set piece."
The result leaves Real four points behind leader Atletico Madrid, and one behind second-place Barcelona, with two rounds remaining. Ancelotti nonetheless maintained that his side will keep fighting for La Liga.
"It will be very difficult but it's still possible mathematically," he said. "We have to win our remaining two games. I don’t care who are the favorites."