Spain boss Vicente del Bosque has conceded that he is unsure on the severity of injuries suffered by David Silva and Alvaro Morata in his side's win over Luxembourg.
The Manchester City midfielder was forced to leave the field in the 11th minute after sustaining a leg injury after being involved in a crunching tackle from Lars Krogh Gerson.
Juventus striker Morata was stretchered off after also suffering an injury to his leg before half time.
Del Bosque told reporters: "I do not know the extent of the injuries.
"Our doctors will inform you when they know something. We know nothing for now."
Spain secured their place in Euro 2016 as a result of their 4-0 win over Luxembourg.