Arsenal boss Arsene Wenger has confirmed Robin van Persie will be out for four weeks.
Van Persie injured his knee scoring at Wembley on Sunday.
Wenger said: "I am not a specialist but he overstretched his knee at the back of his knee when he made the volley [to score on Sunday]. He got kicked or blocked by the defender and overstretched when he hit the ball. In fact we lost Van Persie after 30 minutes, we tried to keep him going in the second half but he was injured.
"It is a ligament at the back of the knee, a tear in the ligament. It is three to four weeks, I take the short delay because I am an optimist but it could be four. As well it is the international break during that period so is it three or four, for us it is the same. We have two weeks to play now and then there is a two-week break because of international games. We have to hope it is only four; he cannot play before the international break, that is for sure. Let's hope he can play after the international break. I listen to what the medical people say to me and you never know, he can have a setback. You can never guarantee."
