Arsenal midfielder Aaron Ramsey will miss the rest of the Christmas schedule after suffering a thigh injury in his side's 3-1 win at West Ham on Thursday.
Ramsey has been a key figure in Arsenal's surprise challenge for the Premier League title and the Wales international's injury is a major blow to the Gunners' hopes.
He limped off in the 65th minute at Upton Park to ruin his 23rd birthday.
Arsenal now face league matches against Newcastle and Cardiff and then an FA Cup tie with north London rivals Tottenham.
"It looks like a thigh strain," Gunners manager Arsene Wenger said.