The Gunners will have to play the rest of the season without one of their key midfielders.
Arsenal have confirmed Mohamed Elneny has undergone successful knee surgery.
The Egyptian star picked up a serious injury in training earlier this month. Despite initial optimism toward his recovery, Elneny had to undergo surgery on Tuesday.
A statement from the north London side reads: “Following an injury sustained in a recent training session, subsequent assessments have confirmed that Mohamed Elneny has a significant injury to his right knee.
“Mo has had successful surgery in London and will be ruled out for an extended period of time.
“A more detailed timescale will be established once the early stages of rehabilitation have been completed.”
Following Elneny’s injury, Arsenal immediately started their efforts to sign a new midfielder.
The Gunners made two bids for Brighton’s Moises Caicedo, but their Premier League rivals rejected both offers. The Premier League leaders then contacted Chelsea over a possible move for Jorginho.
Latest reports from English media claim the two London sides have agreed on a £12m transfer fee for the Italian midfielder. According to BBC, Jorginho will arrive at Arsenal on an 18-month contract with the option of a further year.