Gareth Bale and Luka Modric picked up injuries in Real Madrid's 3-1 win over Malaga.
Bale left with an apparent injury to his left legs in just the fourth minute.
Modric suffered a knee injury.
The injuries come just four days before the second leg of Real Madrid's Champions League tie against Atletico Madrid.
"It's a bad moment for Bale to get hurt. We will have to see what the tests say tomorrow," Emilio Burtagueno said.
"And Modric also worries us. When we only have four days before the quarterfinal return leg, it's not good news."
Via ESPN