Arsene Wenger has confirmed that goalkeeper Lukasz Fabianski is to miss the rest of the season as he requires surgery on a damaged shoulder.
The Poland international has not played since aggravating the problem during the warm-up for the match against Manchester City last month.
It emerged earlier this week that he could remain on the sidelines for a considerable time and the decision has now been taken to send him to Germany for an operation.
"We had bad news for Lukasz Fabianski because he needs surgery on his shoulder," said Wenger.
"He has decided after having seen a few specialists that he will have surgery in Germany. It means his season is over."
Competition for places
Fabianski had begun to establish himself as Arsenal's No.1 with a series of consistent performances prior to the injury and Wenger must now choose between Manuel Almunia and Wojciech Szczesny.
The experienced Almunia has only just returned from a lengthy lay-off and faces a battle to dislodge youngster Szczesny, who has lined up between the posts in recent weeks.
Wenger continued: "The competition for the places at the moment will be between Wojciech and Almunia. Wojciech will play the next game."
Szczesny admitted on Wednesday that he indirectly caused Fabianski's injury during the Man City warm-up.
Meanwhile, midfielder Alex Song (thigh) will not feature against Newcastle on Saturday, but Theo Walcott has recovered from a minor ankle knock picked up in the midweek win over Everton.