Arsenal are again likely to be without playmaker Santi Cazorla for Saturday's trip to Manchester United.
The Spain international midfielder has not featured since picking up an Achilles injury during the 6-0 Champions League win over Ludogorets at the Emirates Stadium on October 19.
And Cazorla has told Spanish radio station Cadena COPE that he is not expecting to return imminently.
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"I still don't know the exact time," said the 31-year-old.
"I am trying to return as soon as possible to be with the team again, but I cannot say if it will be soon, or if I still have a few weeks left.
"I do not know, but hopefully it will be as soon as possible."
Arsenal will assess forward Alexis Sanchez on his return from international duty, but are hopeful the Chile international will be fit for Saturday's crucial Old Trafford encounter.
In-form attacking midfielder Mesut Ozil is sure to be involved and he has challenged his team mates to produce the sort of display which helped them to a 3-0 win over Chelsea in September.
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The German said on Arsenal Player: "[We need to] win every game, get as many points as possible and also be successful against the big teams, like we were against Chelsea.
"We have the quality to beat any team and that's what we want to show this season.
"You can see that the big clubs at the top have quality, and that we have to win every game because of how tight it is at the top.
"Our goal has to be to look at ourselves. If we win the games, we'll be at the top at the end."