Arsene Wenger says it is too early to anticipate how long Aaron Ramsey is going to be out for after ruling the Arsenal midfielder out of Saturday evening's visit of Newcastle.
Welshman Ramsey picked up a hamstring problem after scoring twice in the 4-1 midweek victory over Galatasaray before being forced off at half-time.
We got the scan last night. I don't know enough the extend of his injury. It's a shame
Arsenal manager Wenger said on Friday morning: "We got the scan last night. I don't know enough about the extent of his injury. It's a shame because he was getting close to matching last season's form."
The Gunners are already without England midfielder Jack Wilshere for several weeks with ankle ligament damage, and it remains to be seen how much of the hectic Christmas schedule Ramsey will now miss.
Laurent Koscielny is still struggling with the calf strain he picked up against Southampton and the France centre-half's stand-in Nacho Monreal is still out with a foot injury.
Calum Chambers is suspended after his sending-off against Stoke so fit-again France full-back Mathieu Debuchy could be asked to move inside to partner Per Mertesacker in the centre of the Gunners defence.
Wenger added: "Defensively, I have 24 hours to think about it. I will find a solution for Saturday. We have to play somebody with no experience or somebody who is not used to playing the position."
Young Spaniard Hector Bellerin could retain his place at right-back after playing in the midweek Champions League win over the Turks in Istanbul.
And the Gunners boss said: "He's getting better from game to game. I think at the start he was a bit impressed and a bit inhibited and in the last game I think he played with a bit more freedom."
Wenger, though, feels if all of his rearguard are fully fit come January, then he will not need to dip into the transfer market for reinforcements in that area of the squad.
He said: "If everybody is fit and available, we don't need to go on the transfer market, but we have to consider that there could be a question mark with Koscielny's fitness and we have to go out on the transfer market."
Wenger went on to reveal that he expected a tough challenge from the Magpies but believes his team are also in excellent form.
He said: "They had a great result last week, they are on a good run, so it will be a really interesting challenge for us.
"I think, as well, we have a good dynamic in our team. We have won four of the last five games and we had one blip, it was against Stoke. I think overall we're on a good trend."
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