Mesut Ozil has been ruled out for between 10 and 12 weeks by the German FA due to a knee injury, meaning he could miss up to 16 games for Arsenal.
The German FA announced the news after the midfielder underwent an MRI scan after arriving for international duty with a knee complaint.
The news means Arsenal's growing injury problems have just got a whole lot worse. Arsene Wenger is already without Aaron Ramsey, Serge Gnabry, Mikel Arteta and Theo Walcott in the midfield department. Olivier Giroud, Yaya Sanogo and Mathieu Debuchy are also unavailable.
Whilst Ozil has not displayed his best form since his £42.5m switch from Real Madrid, he absence still comes as a huge blow to the Gunners.
Arsenal's injury list
Arsenal's injury list
1/5 Mikel Arteta (midfield)
Like Diaby, the Spaniard is closing in on a return but the Swansea match will come to soon. The club captain last played in November.
2/5 Mathieu Debuchy (defender)
Returned in the FA Cup semi-final win over Reading but has since been ruled out with injury and Wenger confirmed he remains 'unavailable'.
3/5 Alex Oxlade-Chamberlain (midfield)
Suffered a hamstring injury against Manchester United in the FA Cup and hasn't played since as it has exacerbated a groin problem. Out at least until May and facing surgery in the summer.
4/5 Aaron Ramsey (midfield)
Aaron Ramsey caught a kick on his calf during the win over Hull and was later substituted. The Welshman was rated 50/50 for the Swansea match by Wenger, but it now appears that he is a major doubt for the clash at the Emirates.
5/5 Danny Welbeck (forward)
Danny Welbeck has not played since the goalless draw with Chelsea towards the end of April after suffering a knee injury. Wenger has confirmed that the injury is 'nothing major', and that he should return to full fitness before the end of the season.
Should Ozil be out for a full 12 weeks (an estimation Arsenal do not necessarily agree with) - his return date would be the last day of 2014 - December 31. Here, we take a look at the games he would miss.
Arsenal v Hull, Premier League, Sat 18 Oct
Anderlecht v Arsenal, Champions League, Wed 22 Oct
Sunderland v Arsenal, Premier League, Sat 25 Oct
Arsenal v Burnley, Premier League, Sat 1 Nov
Arsenal v Anderlecht, Champions League, Tue 4 Nov
Swansea v Arsenal, Premier League, Sun 9 Nov
Arsenal v Man Utd, Premier League, Sat 22 Nov
Arsenal v Borussia Dortmund, Champions League, Wed 26 Nov
West Brom v Arsenal, Premier League, Sat 29 Nov
Arsenal v Southampton, Premier League, Wed 3 Dec
Stoke v Arsenal, Premier League, Sat 6 Dec
Galatasaray v Arsenal, Champions League, Tue 9 Dec
Arsenal v Newcastle, Premier League, Sat 13 Dec
Liverpool v Arsenal, Premier League, Sun 21 Dec
Arsenal v QPR, Premier League, Fri 26 Dec
West Ham v Arsenal, Premier League, Sun 28 Dec
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