Martin Ødegaard is expected to be out until at least November's international break due to a knee problem.
The Arsenal captain has been struggling with injuries this season, including a persistent shoulder injury.

What happened to Martin Ødegaard?

Ødegaard became the first player in Premier League history to be subbed off in the first half of three consecutive appearances.
He suffered a nasty clash of knees against West Ham United at the start of October.
The club subsequently diagnosed him with an MCL issue, but didn't provide a timeframe for his recovery.

How long will Martin Ødegaard be out?

Ødegaard will be out until Nov. 23 at the earliest, according to BBC Sport.
The report doesn't provide a definitive return date for the 26-year-old.
There's also doubt over his involvement in the first north London derby of the season immediately after November's international break.

How will Arsenal cope without Martin Ødegaard?

Mikel Arteta's league leaders have fared reasonably well despite only being able to call upon Ødegaard for less than one-third of the available Premier League minutes this season.
Bukayo Saka is back fit and available, having already created six chances from open play.
Right back Jurriën Timber is the team's surprising leader in this metric with seven.
Set-piece specialist Declan Rice already boasts two assists from corner kick scenarios this season.
Summer recruit Eberechi Eze was arguably brought in for this very scenario and has made an encouraging start to life in north London.

What's next for Arsenal and Martin Ødegaard?

Arsenal's skipper is typically the club's most prolific creator, and his absence will be felt over the coming weeks.
He will miss a flood of crucial games, including the first north London derby of the season.
Mikel Arteta will be counting on more telling contributions from his players while Ødegaard is out.
Arsenal's fixtures until November's international break will be a challenge without their captain.
The team will need to step up and perform well to maintain their position in the league.
Martin Ødegaard's injury is a setback, but Arsenal has the talent and depth to cope without him.
The club will be hoping for a speedy recovery and his return to the pitch as soon as possible.