Real Madrid midfielder Toni Kroos has suffered a fractured metatarsal in his right foot, the club have confirmed.
The Germany international has been a regular for the Champions League holders under Zinedine Zidane, playing all 90 minutes of Madrid's last 11 games across all competitions.
But the former Bayern Munich player may not feature again in 2016 after tests carried out in his homeland revealed a fracture at the base of the fifth metatarsal in his right foot.
Kroos - who signed a new six-year deal last month - suffered the injury during Madrid's 3-0 LaLiga win over Leganes on Sunday.
The normal rehabilitation period for a metatarsal fracture is two months, leaving Kroos set to miss the upcoming derby with city rivals Atletico Madrid and almost certain to be out of the Clasico with Barcelona next month, along with Champions League clashes with Sporting CP and Borussia Dortmund.
Kroos' hopes of playing in Madrid's FIFA Club World Cup campaign, which starts on December 15, also look to have been ended.
It means the 26-year-old will also be unavailable for Germany's qualifier with San Marino on Friday and the friendly with Italy four days later.
Questions had previously been raised over Zidane's reliance on Kroos, with the Frenchman saying he was not concerned about him suffering from burnout.
"I'm not worried at all because Toni, even after only one day of rest, is already ready to play in the next game," Zidane said prior to October's 2-1 win over Athletic Bilbao.
But, with Casemiro having not played since breaking his leg against Espanyol in September, Zidane is now short of options in midfield.
Croatia internationals Luka Modric and Mateo Kovacic seem set to fill the void in the absence of Kroos and Casemiro.