Former Real Madrid coach Fabio Capello believes the club's biggest problem is Cristiano Ronaldo and a perceived lack of fitness.
Zinedine Zidane's men have stuttered in LaLiga, with three consecutive draws seeing them slip to second behind city rivals Atletico Madrid.
Ronaldo has only played four of seven league games after a delayed start to his season due to a knee injury, with just a goal and an assist to his name thus far.
And Capello feels that the Portugal captain's lack of fitness is what is costing Madrid, insisting that he is "not well physically".
"The problem for Real Madrid now is Cristiano Ronaldo," he told Onda Cero.
"Because he is not well physically and is their best player."