Zinedine Zidane is unsure whether Gareth Bale will be fit for El Clasico in 11 days' time after the Real Madrid forward suffered an injury to his right ankle during Tuesday's 2-1 Champions League win over Sporting CP.
Bale was caught by a challenge from Sporting centre-back Sebastian Coates early in the second half and, despite attempting to play on after receiving treatment, he departed with 58 minutes on the clock.
LaLiga leaders Madrid host Sporting Gijon this weekend and will hope to have their four-point advantage at the summit still intact when they travel to Camp Nou to face bitter rivals Barcelona on December 3.
"Bale has an ankle problem but he needs a thorough exam tomorrow to see the extent of it," said Zidane after the Sporting match, where Karim Benzema's header three minutes from time secured their passage into the knockout stages of the Champions League.
"It's too soon to say how long he will be out or the size of the problem. We will see, so we don't know if he will be fit for El Clasico."