Cristiano Ronaldo is facing a month on the sidelines after picking up an ankle strain while on international duty.
The 24-year-old attacker returned to Real Madrid on Sunday after suffering the injury in Portugal's 3-0 win over Hungary in Group One of World Cup qualifying.
Ronaldo already had an ankle knock when he linked up with the Portugal squad, and could only manage 27 minutes of the game, with coach Carlos Queiroz receiving some criticism for playing him despite the injury.
A Madrid statement said: "After a clinical examination and an MRI scan, it is confirmed the player has suffered a recurrence of his injury to his right ankle, a medial collateral sprain with inflammation in the bone.
"The estimated recovery time is three to four weeks."