Lukasz Fabianski's thigh injury has put Manuel Almunia back in the frame for Arsenal's Premier League clash against rivals Tottenham at the Emirates Stadium.
Poland goalkeeper Fabianski picked up the injury in the midweek Carling Cup win over Liverpool, while rookie stopper Vito Mannone has made recent mistakes. Gunners boss Arsene Wenger kept Mannone in the team despite Almunia, 32, recovering from a chest problem.
Wenger said: "We lost Lukasz Fabianski with a thigh injury. He will be out for three weeks. Of course, it is big disappointment - because he has just come back from injury.
"Almunia is back to his normal level. I have no worries about him but I don't want to give an indication as to who will play yet. People don't know who the number-one keeper is, but I do.''
Samir Nasri made his return from a fractured leg in the win over Liverpool, although he is cautious about returning to full match-fitness.
"The most important thing is not to make a relapse,'' said the France midfielder. "The boss asked me two or three times during the game how I felt and I had to make a sign if I felt the slightest touch. But everything was all right.
"I was very satisfied with my comeback. After five months without playing, I had appetite, I wanted to get around the pitch and touch the ball. I thought that it would have been a little bit more difficult. We worked well with the physical assistant. Now, I need to play and play again.''
Nasri is hoping his side can display the form they had before recent draws against AZ Alkmaar and West Ham.
"It was a small disappointment to drop two points while we led 2-0 at West Ham,'' he said. "We had the same against Alkmaar and we need to correct that but we were almost invincible for 10 games before that.
"Now it is necessary to win again in Premier League. And there is nothing better than a derby against Tottenham. It's been a while since both teams met each other while so high in the table.''