Shkodran Mustafi had started 12 of Arsenal's last 15 Premier League games under coach Mikel Arteta.
London - Mustafi suffered a hamstring injury during Arsenal's 2-0 semifinal win over Man City on July 18.
Arsenal defender Shkodran Mustafi will be missing the start of next season after undergoing surgery for his hamstring injury, the Premier League club has confirmed.
Mustafi sustained the injury during Arsenal's 2-0 semifinal win over Manchester City at Wembley on July 18. Arsenal were strong in their defence against City, with Mustafi and David Luiz proving key performers in that game.
"Right hamstring injury sustained during Emirates FA Cup semifinal on July 18. Further assessments during the week identified a significant injury to the right hamstring," Arsenal said in a medical update on Tuesday.
"As a result, Shkodran had a successful small procedure to his right hamstring on Saturday. Shkodran is now in the early stages of his recovery and rehabilitation, receiving specialist attention and support from our medical team.
"Aiming to return to full training in October," it added.
The 28-year-old, who arrived at the club from Valencia in 2016, has received plenty of criticism for his inconsistent displays. However, under Mikel Arteta, he has started 12 of Arsenal's last 15 Premier League games.
The FA Cup final against Chelsea, scheduled to be played on Saturday, will be the Gunners' only chance to secure the ticket to Europa League.