New Deportivo La Coruna striker Joselu may have suffered knee ligament damage on his debut for the club.
Joselu, a loan signing from Stoke City, had to be replaced after 24 minutes against Athletic Bilbao after being on the receiving end of a crunching tackle from Raul Garcia.
The 26-year-old attempted to carry on, but his right knee was in clear discomfort and he was forced to limp off.
The Galician club are set to carry out further tests on the knee in the coming days to uncover the full extent of the damage.
Defender Sidnei will also be examined after being forced off with a thigh injury.