Real Madrid will assess forward Gareth Bale after the Wales international was forced to leave the field early in Tuesday’s win over Sporting Lisbon.
The 27-year-old limped out of the 2-1 victory in Portugal with an ankle injury as the Spanish club booked their place in the last 16 of the Champions League.
Raphael Varane and Karim Benzema both got their names on the scoresheet to ensure the defending champions would progress and they can now secure top spot in Group F if they beat Borussia Dortmund in the final match.
However, news of Bale’s injury will come as a huge blow as Los Blancos look to maintain their strong challenge in La Liga.
Real saw off city rivals Atletico Madrid 3-0 last weekend and currently sit four points clear of Barcelona at the top of the table.
The European champions face Sporting Gijon this weekend before travelling to Barcelona in El Clasico on December 3.
The club’s medical staff will now bring in Bale for some tests as they look to learn the severity of the injury.
Boss Zinedine Zidane said: “He suffered more of a twist than a knock, but we will have to wait and see what the problem is.
“On Wednesday, he will be examined by our medical staff and after that, we will find out more.”
Real Madrid are now on a run of 30 games unbeaten in all competitions and can be backed at 1.06 to extend that form on Saturday, while travelling side Sporting Gijon are priced at 41.00 to cause an upset and the draw can be backed at 11.00.