Arsenal have been dealt a major injury blow ahead of Saturday's trip to Manchester United with the news full-back Hector Bellerin has been ruled out for four weeks.
Bellerin sustained the problem in the closing moments of the 1-1 draw against Tottenham on November 6 and subsequently withdrew from the Spain Under-21 squad.
Gunners manager Arsene Wenger, speaking at his news conference on Thursday, confirmed the defender was set for a spell on the sidelines.
He said: "Hector is out for four weeks, he got injured in the last 10 seconds after a strong challenge from Danny Rose."
There was better news, however, on Alexis Sanchez, who Wenger believes emerged unscathed after playing for Chile on Tuesday.
The forward missed the game against Colombia last week after suffering a hamstring injury in training and Wenger demanded Arsenal's medical staff were given permission to view the MRI scans to prevent a "suicidal decision" over his star's fitness.
Sanchez played against Uruguay on Tuesday and Wenger will now wait for the 27-year-old to return to England before assessing whether he will be a part of the squad at Old Trafford at the weekend.
Wenger said: "He texted us to tell us he's in good shape after the game. We have to wait and see him tomorrow morning and see if he can work in the squad or not.
"I will consider the risk of injury because he played with a hamstring problem."
Asked about Chile's conduct over the past week, Wenger was diplomatic, adding: "It's very difficult to make a definite assessment on that because I don't know how bad his injury was.
"I understand Alexis is keen to play for his country in such an important game.
"It's a different period because it's the first time where players have played many games. It's a period that often decides the championship.
"Last year we lost important players in November."
