Arsenal manager Arsene Wenger says it is too early to say how long midfielder Aaron Ramsey will be on the sidelines with a hamstring injury.
Ramsey's stunning goal lit up Tuesday's 4-1 Champions League win at Galatasaray but the 23-year-old was taken off at half-time as a precaution.
He has now been ruled out of Saturday's home game with Newcastle United.
"We got the scan last night, I don't know enough to give the extent of his injury," Wenger said.
Arsenal are already without midfielder Jack Wilshere, while defensively they are also struggling with Laurent Koscielny (calf), Nacho Monreal (ankle) and Calum Chambers (suspended) all unavailable for the Magpies' visit to the Emirates Stadium.
Wenger has recalled Francis Coquelin from his loan spell at Charlton Athletic to boost his options in midfield.
The manner of his side's win in Turkey in midweek has eased some of the pressure on the Frenchman and he insists his team is heading in the right direction.
"We have a good dynamic in our team," he said. "We've won four of the last five games. I feel we're on a good trend.
"We are united. Our one target is to do well for the club we love. That's all we want to achieve."
Wenger on the 'Arsene Wenger Stadium'
Newcastle manager Alan Pardew said this week that the Emirates should be renamed in honour of Wenger.
"I'm very thankful for compliments but I don't want anything. I want only to do well in my job for this club.
"I don't say it wouldn't mean anything to me but I don't demand anything, other than from myself."
Wenger on Alan Pardew
Wenger and Pardew had a famous touchline spat in 2006 but the Frenchman says that is all forgotten now.
"We had a problem one time and afterwards we sorted it out. He's done very well - he's come through a difficult patch at Newcastle with strength and dignity."
Wenger on Lukas Podolski
The Germany international has been linked with a move away from the club after failing to secure a regular starting role but scored twice in the win over Galatasaray.
"He's getting back in good form. There's a lot of competition up front. We have all the players available so can rotate a little bit. He will get his opportunities.
"I can understand frustrations of players who are top players but not playing. But you always have to be ready for when you can help the club."