Arsenal face an anxious wait over forward Alexis Sanchez after he limped out of training with Chile with a muscular injury.
Sanchez was forced to the sidelines during a session at Chile's training camp with what appeared to be a calf problem.
A statement from the Chile FA read: "The medical corps of the Chilean national team informs the player Alexis Sanchez has a low-grade muscle injury.
"The athlete will stay in Santiago, under treatment and evaluation, before the meeting of Chile and Uruguay."
Chile travel to Colombia for a World Cup Qualifier on Thursday, which Sanchez will miss, and then return home to face Uruguay on November 15.
Arsenal have a busy spell of games coming up after the international break, and losing Sanchez for any length of time would be a massive blow.
They take on Manchester United at Old Trafford on Saturday week and then host Paris Saint-Germain on November 23 as they look to put their stamp on top spot in Champions League Group A.
The 27-year-old has scored eight times in all competitions this season, including goals against PSG and Ludogorets in Europe.