Real Madrid left-back Marcelo is a doubt for the looming Clasico clash with Barcelona after limping out of Tuesday's Champions League 1-0 Group A win over Paris Saint-Germain with a hamstring injury.
The Brazilian picked up the problem midway through the first half of the game at the Bernabeu, and was replaced by versatile defender Nacho Fernandez, who scored the night's only goal just two-and-a-half minutes later.
Madrid did not immediately release an official statement regarding the injury, however Madrid coach Rafa Benitez said in his postmatch news conference that it was a hamstring problem. The player himself said he was "fine" while passing through the mixed zone, but did not give any further details.
The club vice-captain has played 90 minutes in 12 of Madrid's first 13 games in all competitions this season, and scored crucial goals in recent La Liga wins against Levante and Celta Vigo.
However, he now looks set to miss Sunday's La Liga game at Sevilla, and will be a doubt for Brazil's World Cup 2018 qualifiers in Argentina on Nov. 12 and at home to Peru on Nov. 17.
With Madrid having no immediate replacement in their squad, Marcelo now faces a race against time to be fit for Nov. 21's Clasico against Barcelona at the Bernabeu. Potential replacements Alvaro Arbeloa and Dani Carvajal are also currently injured.
Keylor Navas, Pepe, Luka Modric, Mateo Kovacic, James Rodriguez, Gareth Bale and Karim Benzema have all missed games recently with muscle strains or tears.
But Benitez has regularly denied any issues with the club's medical staff, saying the run of injuries was not uncommon for big clubs with lots of important fixtures.