Real Madrid boss Carlo Ancelotti has admitted that his players have been flagging in recent weeks.
The Spanish giants appear to have blown their title hopes with some poor results.
Ancelotti said: “Our mental energy has failed us over the last two games and I can see the team are mentally tired.
“There is nothing wrong with their physical condition.
“It’s not easy to recover your mental energy between Champions League semi-finals, and that energy is very important at that stage of the season.”