Atlético Madrid forward Félix has been ruled out for up to one month with a knee injury, the club have announced.
The Spaniard was forced off in the second half of Sunday's La Liga match against Valencia after sustaining an injury during the first half.
He will now undergo further scans and is likely to be sidelined until at least February, when he is scheduled to return from his international call-up.
Felix, who joined Atletico from Real Betis last summer for £27m, made just two starts for the club before being ruled out on Saturday night.
The 24-year-old has scored three goals in 15 appearances this season and has been an important player for the side under head coach Diego Simeone.
The news comes as a blow for Atletico, who were looking to maintain their position in the top four in La Liga and secure a place in the Champions League next season.
It also means that they will be without their leading scorer for at least the next month, which could leave them vulnerable in the league and potentially in Europe.
However, it is not yet clear whether Felix will be able to play again before the end of the year or even the start of the new season.
In the meantime, the team will need to find a way to cope without him and hope that he can recover quickly and make a full recovery before returning to action.
Overall, it is a big setback for Atletico and their chances of competing for major honours in the coming months.
But it is also a reminder of how fragile football can be and how injuries can happen to anyone, regardless of their level of ability or experience.