Arsenal midfielder Aaron Ramsey has been ruled out of Tuesday's Champions League match at Borussia Dortmund after injuring his ankle in training.
Gunners boss Arsene Wenger revealed the 20-year-old Wales international limped out of training on Monday ahead of the team's flight to Germany.
It deprives Arsenal of another first-choice midfielder, with Jack Wilshere also sidelined with an ankle problem.
Ramsey was out for nine months after breaking his leg in February 2010.
He suffered fractures to the tibia and fibula of his right leg following a tackle by Stoke's Ryan Shawcross during a Premier League game at the Britannia Stadium.
However, having spent loan spells with Nottingham Forest and former club Cardiff City, he declared himself fully fit and hopeful of a positive season.
Ramsey has started all six of Arsenal's matches so far this season, including their first Premier League victory of the campaign, Saturday's 1-0 win over Swansea at Emirates Stadium.
New midfield recruits Mikel Arteta and Yossi Benayoun made their Gunners debuts at the weekend and both are included in the 18-man squad for Tuesday's match.
Alex Song and Emmanuel Frimpong provide alternative options in central midfield for Wenger.