Gerard Pique went off injured in the first half of Barcelona's La Liga match against Athletic Club.
The centre-back went down after an aerial duel with Alex Berenguer at the half-hour mark of the clash in Bilbao.
He was taken off shortly afterwards and replaced by 22-year-old Ronald Araujo.
What has happened?
Barca coach Ronald Koeman said in his pre-match press conference that the 34-year-old had been suffering from "minor annoyances" but had trained as normal this week.
But the defender has become increasingly unable to finish matches for the Camp Nou outfit.
This is the sixth time he has been taken off in his last 13 starts in La Liga, which is the same number of times he had been substituted in his previous 111 starting XI appearances.