Barcelona striker Lionel Messi has been ruled out for up to eight weeks after suffering a tear in his left hamstring.
The Argentina international limped off after 20 minutes in Barca's 4-1 win at Real Betis on Sunday.
Messi has struggled with hamstring problems throughout the season, although he has only missed three games in the campaign so far.
However, the 26-year-old now faces a lengthy spell on the sidelines.
A statement on Barcelona's website read: "Tests carried out on Lionel Messi this morning (Monday) have confirmed that the player has a muscle tear in the femoral biceps of the left leg.
"The estimated recovery time is between six to eight weeks. The first part of the recovery will take place in Barcelona and the second part in Buenos Aires."
The injury relates to a specific muscle involved with sprinting and Messi has suffered the problem three times this season.
Messi has scored 14 goals in all competitions this season, but his form has come under scrutiny after five scoreless La Liga outings.
Barcelona are still unbeaten in both domestic and European competition despite Messi's dip in form, and sit three points clear at the top of La Liga as they look to retain their Spanish crown.
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